Academic censorship on sci.physics.research?
Sabbir Rahman
It is with some disappointment and reluctance that I am forwarding
this message to the sci.physics and sci.physics.relativity newsgroups,
which are unmoderated. I hope, nevertheless, that it will be given due
consideration by those readers of this newsgroup who are open-minded
and sincere enough to seek scientific truths even if they seem to go
against their mathematical or physical "intuition".
On 19th July, 2001, a rather scathing attack was made by Chris Hillman
on the work of Abhas Mitra, regarding the formation and existence of
black holes (or rather, lack thereof). This is still available on the
sci.physics.research archives:
http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
Note that the tone used in this email is quite intolerant and
undignified, being full of personal attack and "flames" and is
clearly quite contrary to the charter of the sci.physics.research
newsgroup. Nevertheless, the moderators of the sci.physics.research
newsgroup (John Baez and Matt McIrvin) accepted Hillman's posting for
distribution. Note that John Baez is currently hosting Hillman's
relativity website, so one can safely presume that the three of them
know each other fairly well.
I made Abhas Mitra aware of Hillman's posting, and he prepared a
detailed rejoinder to it, including mathematical details, which I
forwarded to the newsgroup. This rejoinder was rejected by the
moderator, Matt McIrvin, on the basis that it contained "personal
attacks" against Chris Hillman. This of course was surprising, as
(i) Mitra's rejoinder was a completely justified and direct response
to Hillman's abusive posting, and (ii) was much tamer in content
besides, with logical mathematical arguments being presented to show
the mathematical misconceptions in Hillman's original posting.
Both Abhas Mitra and myself independently complained to Matt McIrvin,
expressing our surprise at his rejection of the rejoinder. To this
we have yet to have, nor do we any longer expect, a response. Matt
McIrvin did suggest that if we sent a version without the personal
attacks, he would consider it for posting. On this basis I prepared a
second version (appended below). This has neither appeared on the
sci.physics.research newsgroup, nor has McIrvin had the courtesy to
give an explanation as to why.
The moderators of the sci.physics.research website are quite clearly
guilty of double-standards here. Apparently it is fine to publish
inflammatory articles so long as they are protecting established
physical preconceptions - and clearly it is fine to censor ideas
which would seem to contradict these established preconceptions).
Scientists, and indeed communities of scientists have often made
mistakes or had serious misconceptions in the past. This human
attribute is of course not limited purely to science.
It would be reassuring if we were to see some humility and willingness
to accept this human fallibility amongst our scientists - no matter how
intelligent or how objective we may hold *ourselves* to be. Arrogance
and prejudice are no replacement for honesty and sincerity in searching
for scientific truth, no matter where or what its source.
To the end of this introduction, I have attached the edited rejoinder,
as well as Chris Hillman's original, and the original rejoinder. I
will let the readers judge for themselves on the matter.
Sincerely yours,
Sabbir Rahman.
----------------------------------------------------------------------
***EDITED REJOINDER***
----------------------
Having made Prof Abhas Mitra aware of the postings to the newsgroup
sci.physic.research regarding his work on the non-existence of black
holes, he has kindly prepared the following rejoinder. He has asked me
to edit the English and forward it to the newsgroup on his behalf. I
would request that any questions be sent to Prof Mitra directly - as I
understand it he does not have access to newsgroups and has certainly
never posted to one before. I have cross-posted this message to
sci.physics.relativity as the contents are obviously relevant to this
newsgroup as well.
The only changes made to Prof Mitra's original are fairly minor
spelling and grammatical changes to clarify the meaning where this may
have been unclear. Non-trivial adjustments requiring some element of
personal interpretation of the originally intended meaning have been
placed in square brackets, though the resulting text has been kept as
faithful to the original as possible. The equations and mathematical
arguments should, however, have remain unchanged.
For reference, the original posting by Chris Hillman to which this
reply is addressed can be found at:
http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
There seems to be some confusion regarding Prof Mitra's academic
background. So to clarify these on his behalf: Abhas Mitra is a
theoretical high-energy astrophysicist by training. His PhD thesis was
entitled "A New Theory of Ultra High Energy Gamma Ray Production in
Cygnus X-3" from the University of Mumbai, India. He was a full member
of the American Astronomical Society from 1993-95, is a member of
the International Astronomical Union and has been a life member of the
Astronomical Society of India since 1983. He has published many papers
in journals such as Astrophysical Journal, Astronomy and Astrophysics,
and Physical Review Letters. He has been an invited speaker on various
topics of High Energy Astrophysics in many conferences, and has worked
as a referee for the Astrophysical Journal amongst others. As far as
research on the physics of the Central Engine of Gamma Ray Bursts is
concerned, he happens to be the only individual having publications in
refereed journals.
Sincerely,
Sabbir.
P.S. The original rejoinder by Mitra understandably contained some
personal comments regarding Hillman's method of "critique" which are
not necessarily relevant to the matter under discussion, so I have,
at the request of the moderator, removed such comments as far as
seems reasonable.
----------------------------------------------------------------------
From: Abhas Mitra, ami...@apsara.barc.ernet.in
Newsgroup: sci.physics.research, sci.physics.relativity
Subject: Rejoinder to Hillman's posting entitled "Black Hole Preprints
by Abhas Mitra"
None of the various posting(s) made by Chris Hillman to this forum [can be
said to be] a scientific critique of my preprints/reprints related to the
non-occurrence of finite (gravitational) mass Schwarzschild Black Holes (BHs),
for the following basic reasons:
(i) It seems that he has not read my papers properly and has attributed
or implied several aspects which are not contained in my papers. Neither does
he appear to have made any sincere attempt to understand whatever portions he
might have read.
Some of the comments posted in this forum by others are also likely to have
been based [solely] on reading of the abstract. [For example], someone
[referred to as] "zirkus" wrote, "I have not looked at the following paper
but, according to its abstract...".
(ii) Most of my preprints are based on simple and exact analytical calculations
(WITHOUT ever involving a single assumption or simplification) and associated
equations. A meaningful critique of such works must point out the definitive
errors/shortcomings in specific equations, quoting specific equation numbers.
If there is a conceptual error, a meaningful critique must point out which
specific equation is based on those conceptual errors, or else provide an
interpretation of which equations have been [derived or used] incorrectly.
But as one can see, Hillman has been unable to point out any such specific
error.
(iii) In the following, I shall show that whatever little analytical elements
(non-numbered equations) there [happen to be] in the critique by Hillman,
actually CORROBORATE the results of my preprints.
1. One of my previous preprints (gr-qc/9807197) tried to show that:
If we follow the radial geodesic of a test particle around a BH using any
coordinate system including Lemaitre coordinates (r, t, t=comoving time),
the geodesic, which must be TIMELIKE (ds^2 >0) at any non-singular region
of spacetime, would become null (ds^2=0) at the Event Horizon (EH) at
R=R_g=2M. Hillman asserts that my derivation to this effect is incorrect
because "Part of Mitra's confusion throughout his preprints rest upon
persistent failure to distinguish clearly between coordinate slopes and
physical velocity...".
While he makes this accusation, note that he has NOT pointed out which
EQUATION is based on such "confusion" and in turn, which specific result
is incorrect because of such "confusion". He has unnecessarily
introduced the "Painleve chart", and claims, WITHOUT ACTUALLY SHOWING IT,
how the "Painleve Chart" disproves my result. For the benefit of the
serious readers, I give below the essence of my proof:
In Lemaitre coordinates, the radial geodesic (angular part=0), the metric
of a test particle around a BH is
ds^2 = dt^2 - g_rr dr^2 (1)
where
g_rr = [(3/2R_g) (r-t)]^{-2/3} (2)
The invariant circumference coordinate R is related to r, t in the following
way:
R = [(3/2R_g) (r-t)]^{2/3} R_g (3)
Thus at R=R_g (2M),
[(3/2R_g)(r-t)]^{2/3} = 1 (4)
Using Eq.(4) in Eq.(2), we find that,
g_rr = 1 at R = R_g (5)
Using Eq.(5) in Eq.(1), we have
ds^2 = dt^2 - dr^2 at R=R_g (6)
Note that while he uses the symbol "r" for circumference coordinate, I am
using "R" for the same; also while Hillman uses "m" for the gravitational
mass of the BH, I use "M" for the same.
We would require here a standard result:
dR -(1-2M/R)
--- = ---------- [E^2 -(1-2M/R)]^{1/2} (7)
dT E
where E is the conserved energy per unit rest mass of the test particle.
Since t is the comoving time, we have
dt = (1-2M/R)^{1/2} dT (8)
Now by using the above equations, it can be found that,
(dr/dt)^2 = 1 at R = R_g (9)
Hillman also writes that "it is true that the coordinate slope equals to
-1 here"; by 'here' he means at R=2M. To verify the correctness of
Eq.(9), however, it would be better to see the Eq. 3.12.5, pp. 112 of
Zeldovich and Novikov, Rel. Astrophysics, Vol. 1, Univ of Chicago (1971):
(dr/dt) = +/- (R_g/R)^{1/2} (3.12.5) of ZN
Note that the tau of ZN is our t, r of ZN is our R and vice-versa, and
recall that we have taken c=G=1.
By putting Eq.(9) in Eq.(6) one can find that INDEED
ds^2 = 0 at R=R_g=2M following the radial geodesic. (10)
If the EH R=R_g were a mere coordinate singularity and actually a regular
region of spacetime, GTR demands that the geodesic must remain timelike
there and we should have had ds^2 > 0. Thus Eq.(10) implies that the
R=2M is NOT a non-singular region of spacetime. [Rather], it corresponds
to a true physical singularity. But, for a BH, we know that the true
physical singularity is at R=0. Therefore we can reconcile Eq.(10) with
this knowledge by recognizing that we must have
R = R_g = 2M = 0 (11)
In other words, the mass of the BH must be
M = 0 (12)
Note that at no point in this proof do we mention "physical velocity" and
neither is there any "confusion" between "coordinate slope" and "physical
velocity".
2. In Sec 3 of his posting, Hillman writes that "Mitra claims that the
Kruskal-Szekers chart has a coordinate singularity at R = 2M; this absurd
(and very incorrect) conclusion..."
Now the fact is that, I HAVE NEVER EVER MADE SUCH A CLAIM IN ANY OF MY
PREPRINTS. On the other hand, I have pointed out, in several of my
preprints, that even if one uses the Kruskal coordinates u and v, one
would find that the EH is a true physical singularity. In other words, I
have derived Eq.(10) using [these] coordinates. In fact, I have done so
in a most straightforward manner using Schwarzschild coordinates too. For
the benefit of the serious readers, I shall, again, give below the
essence of my proof that (du/dv)^2 =1 at R=2M in this regard:
In one of his earlier postings [webpages?] entitled "Hall of Shame",
Hillman had ridiculed my work without even attempting to put up any
scientific critique. All that he could say was to mention a preprint,
(astro-ph/9905144), by I. Tereno which had scientifically, albeit
erroneously, criticised my preprint. Nevertheless, here Hillman had
conveniently forgotten to mention any of my REBUTTALs to Tereno's work:
A. Mitra, astro-ph/9904163 and 9905329
Anyway let me proceed with my proof:
From Eq.(7), it follows that, dR/dT = 0 at R=R_g=2M. And since dT is an
infinitesimal quantity by definition (not to be confused with delta T,
which could be finite or even infinite), we have
dR = 0 at R=R_g=2M along a radial geodesic (13)
The Kruskal coordinates obey, everywhere in the Kruskal diagram, the
equation
u^2 - v^2 = (R/2M -1) exp (R/2M) (14)
so that,
u^2 = v^2, (v/u)^2 = 1 at R=2M (15)
Now differetiating Eq.(14) w.r.t. R, and using Eq.(13) on the LHS, it
follows that
u du - v dv = 0 at R=2M (16)
Or,
(du/dv)^2 = (v/u)^2 at R=2M (17)
Invoking Eq.(15) in Eq.(17), we see that
du^2 = dv^2 at R=2M (18)
Now for a radial geodesic, it can be seen that the Kruskal metric at
R=2M is:
ds^2 = (16M^2/e) (du^2 - dv^2) (19)
Invoke Eq.(18) here and obtain
ds^2 = 0 at R=2M along a radial geodesic (20)
Again note that this proof neither involved any mention of "physical
velocity'' or any associated "confusion". Hillman unnecessarily and
irrelevantly invokes the "Lambert W function" without showing how the
W function or any other function would actually disprove my Eqs. 13-20.
Here Hillman has used two variables "R" and "T" without even mentioning
what they are (note that I use R and T for Sch. coordinates);
presumably they are proportional to our u and v. For the radial part of
the metric, Hillman too finds, through a convoluted route using the
"Lambert W function" that at the EH
ds^2 = (8m/e) (-dT^2 + d R^2) , R and T not defined by Hillman.
By comparing with Eq.(19), it seems that R= 2m u and T =2m v (at least
at the horizon). Then, we would have (dR/dT)^2 =1 at the EH, and
Hillman's Eq. too would give ds^2=0 at the EH. As explained earlier,
this would mean that the mass of the BH, M=0.
3. Since Hillman has been unable to point out any real error in any of
my preprints, he goes on citing one standard book after another (without
showing how those books actually negate my precise derivations). If at
any given point of time, the existing scientific literature and
interpretation of laws of Nature were the ultimate without leaving scope
for new analysis and interpretations, there would not have been any
scientific or intellectual progress, and, intellectually, we would have
continued to be like the prehistoric cavemen.
My criticism of the Oppenheimer-Snyder paper is based on the fact Eq.(36)
of it overlooked the fact that the ARGUMENT OF A LOG FUNCTION CANNOT BE
NEGATIVE. This statement cannot be negated by citing books and pouring
forth ridicules. And this statement demands that during the collapse of
the dust-ball, we must have
2M/R < = 1 (21)
This mathematical result means that TRAPPED SURFACES DO NOT FORM in the
O-S dust collapse. As I have shown (astro-ph/9904163, 9910408), unless
Eq.(21) is incorporated into the O-S analysis, the behaviour of the
metric coefficients would be inconsistent and unphysical at R=0.
Here Hillman makes mention of the "Vaidya null-dust" without knowing
that Prof. P.C. Vaidya himself has found my work to be completely
correct.
4. Hillman writes that "Mitra claims that the well-known 'trapped
surface' singularity theorem is false! The correct statement and proof
can be found in.."
Firstly, I never mentioned "trapped surfaces" as singularities.
[Secondly,] it appears that Hillman is unaware of the fact that the
well-known singularity theorems are based on several ASSUMPTIONS. The
most crucial assumption here is that there is a "trapped surface" in
the spacetime. Now when, by definition, existence of "trapped surfaces"
is an ASSUMPTION how can any book PROVE the existence of trapped
surfaces?
On the other hand, I have actually proved, in a general manner, for
spherical collapse of baryonic matter, that trapped surfaces do not form
at all. In other words, I have shown that the crucial assumption behind
the singularity theorems is incorrect (for collapse of isolated bodies).
And since the essence of my proof is so straightforward, for the
serious readers, I present it below:
All spherical collapse involving baryonic matter and radiation obey (see
ref. in my paper) a relation
Gamma^2 = 1 + U^2 - 2M/R (22)
where
Gamma = dR/dl (23)
and dl is an element of proper length along the radial worldline of the
collapsing fluid. Also,
U = dR/d tau (24)
where d tau is an element of proper time following the fluid element.
Clearly, Eqs.(23) and (24) are correlated as
U = Gamma V (25)
where
V = dl/d tau (26)
and let us treat V as a pure symbol.
By putting Eq.(25) in Eq.(22) and by transposing, we have
Gamma^2 (1- V^2) = 1 - 2M/R (27)
Now by using the result that the determinant involving the metric coeff.
of any metric must be negative, I have shown that, if (1-V^2) is negative,
then so must be Gamma^2, so that the LHS of Eq.(27) is always positive.
Then it follows that
2M/R < = 1 (28)
a result obtained independently from the O-S work. Eq.(28) shows that, if
the fluid [were to] collapse to a singularity at R=0, under positivity of
mass, one must have
M-->0 as R-->0 (29)
5. The preprint astro-ph/9910408 was published in Foundation of Physics
Letters and this has obviously greatly disappointed Hillman and others.
If they are so sure that it is all wrong, I would suggest that they
submit an academic critique of my paper to Foundations or any other
standard refereed journal.
This paper was published in Foundations after several referees failed to
point out any specific errors in my work, after some referees found that
the work is "mathematically" correct, and eventually after two anonymous
referees recommended its publication with some revisions. This is hardly
a "very regrettable" or "shame shame" procedure.
6. Hillman's posting started with criticism of my work hep-th/9905182.
In this work I never claimed that non-extremal BHs with mass M>Q (charge)
are not exact GTR solutions, as implied by Hillman. In fact they are as
exact solutions as the Schwarzschild BHs. But if one starts with a M>Q
case and slowly reduces Q to Q=0, one should recover the Sch. BH. In such
a case, one would obtain a finite mass M>0 BH. But since I have already
shown, by several independent modes, that the only allowed value of M is
0, eventually, it is [only] the extremal BHs with M=Q solutions which are
to be accepted because they lead to the correct result M=0 when Q=0.
I invite Hillman and all other readers to write a proper scientific
critique pointing out specific errors in my equations and interpretations
in case any of them think that my work is erroneous. Incidentally, through
email, I have repeatedly requested Profs. S. Hawking. R. Penrose, K.Thorne,
C.W. Misner and many others to send their critique, if any, to me. But none
of them have acted so far.
---------------------------------------------------------------------------
***HILLMAN'S ORIGINAL***
------------------------
Black Hole Preprints by Abhas Mitra [Was: charged black holes]
--------------------------------------------------------------------------------
Subject: Black Hole Preprints by Abhas Mitra [Was: charged black holes]
From: Chris Hillman <hil...@math.washington.edu>
Date: 19 Jul 2001 16:31:20 GMT
Approved: s...@rosencrantz.stcloudstate.edu (sci.physics.research)
In-Reply-To: <uO%37.19419$Kf3.2...@www.newsranger.com>
Message-ID:
<Pine.OSF.4.33.010717...@goedel3.math.washington.edu>
Newsgroups: sci.physics.research
Organization: University of Washington
References: <9id6d1$m3...@rs04.hrz.uni-essen.de>
<29b67412.01071...@posting.google.com><uO%37.19419$Kf3.2...@www.newsranger.com>
--------------------------------------------------------------------------------
On Sat, 14 Jul 2001, Squark wrote:
> On Sat, 14 Jul 2001 03:14:25 GMT, zirkus wrote (in
> <29b67412.01071...@posting.google.com>):
>
> >Btw, I have not looked at the following paper but, according to its
> >abstract, GTR only admits the existence of extremal black holes and
> >the paper might discuss how this result is related to string theory:
> >
> >http://arxiv.org/abs/hep-th/9905182
This preprint is by Abhas Mitra, a nuclear physicist by training, who
apparently likes to claim expertise in astrophysics. But, unfortunately,
when it comes to gtr there is no simply polite way of describing his level
of understanding, which literally does not rise to what is expected of
-undergraduate students- taking a first course in gtr (c.f. the well known
textbook by Schutz).
-Of course- Mitra is flat out wrong. Specifically:
(1) Mitra claims that gtr only allows extremal Reissner-Nordstrom
electrovacuums (q = m in relativistic units in which G = c = 1)! In fact,
any decent undergraduate student of gtr can easily check that the
subextremal (q < m) RN hole is a perfectly legitimate exact electrovacuum
solution to the EFE; that is, it solves the Maxwell source-free field
equation on curved spacetime and also the Einstein tensor matches the EM
stress-energy tensor, so the RN electrovacuum models a the exterior
fields, both electric and gravitational, of a massive charged object.
The maximal extension has a global conformal structure
http://math.ucr.edu/home/baez/RelWWW/history.html
which Mitra doesn't like (or understand), but no matter how many preprints
he posts to LANL claiming otherwise, he cannot change the fact that it
-is- a perfectly legitimate exact solution to the Einstein-Maxwell field
equations. Indeed, a standard problem for beginning students of gtr is to
-derive- the this electrovacuum. See for example the discussion of the RN
electrovacuum in this review paper
http://xxx.lanl.gov/abs/gr-qc/0004016
or in the well-known monograph
Stephen W. Hawking and G. F. Ellis,
The Large Scale Structure of Space-Time.
Cambridge University Press, 1975.
In print, ISBN 0-521-09906-4; list price $47.95 (paperback)
or in widely used gtr textbooks such as
Ray A. d'Inverno,
Introducing Einstein's Relativity
Oxford University Press, 1992
In print, ISBN 0-19-859686-3; list price $42.95 (paperback).
Charles W. Misner, Kip S. Thorne, and John A. Wheeler,
Gravitation,
W. H. Freeman & Company, 1973.
In print, ISBN 0-7167-0344-0; list price $63.95 (paperback).
as well in as these high quality on-line course notes:
http://math.ucr.edu/home/baez/RelWWW/grad.html#gr
http://xxx.lanl.gov/abs/gr-qc/9707012
Mitra has posted many other c---ky preprints to the LANL server, including
http://arxiv.org/abs/astro-ph/9904162
http://arxiv.org/abs/astro-ph/9910408
in which, as anyone can easily verify:
(2) Mitra claims that the tangent vectors to a timelike geodesic in the
Schwarzschild vacuum must become -null- at the event horizon r = 2m; this
is of course completely incorrect! One need only start with -any-
timelike vector at r = 2m and evolve backward in time a timelike geodesic,
parametrized by proper time, by using this initial data in the geodesic
equations. Mitra appears to be completely unaware of the Painleve chart
ds^2 = -dt^2 + (dr + sqrt(2m/r) dr)^2 + r^2 (du^2 + sin(u)^2 dv^2)
-infty < t < infty, 0 < r < infty, 0 < u < pi, -pi < v < pi
in which it is very easy to find explicitly the world lines of "LeMaitre
observers", namely
r(t) = (9m/2)^(1/3) (t0-t)^(2/3),
-infty < t < t0
Here, r(t1) = 2m for t1 = t0-4m/3, and it is true that the -coordinate
slope- dr/dt equals -1 there, but if you draw the -light cone- there using
the LeMaitre ONB of vectors
e_1 = d/dt - sqrt(2m/r) d/dr
e_2 = d/dr
e_3 = 1/r d/du
e_4 = 1/(r sin(u)) d/dv
(to draw the light cones in the tr plane, use the null vectors e_1 + e_2,
e_1 - e_2), or if you simply compute the squared magnitude of the tangent
vector, you will see that of course this tangent vector is -timelike-, not
null! Part of Mitra's confusion throughout his preprints rests upon
persistent failure to distinguish clearly between coordinate slopes and
physical velocity measured relative to some "very close" observer (e.g.,
defined by the unit timelike vector X = e_1 in an ONB, such as the
LeMaitre ONB).
(3) Mitra claims that the Kruskal-Szekeres chart has a coordinate
singularity at r = 2m; this absurd (and very incorrect) conclusion may
also be very quickly debunked: it is easy to write the K-S chart in closed
form, without the constraint (used in most textbooks) which confuses
Mitra, by using the "Lambert W function":
m^2 W[(R^2-T^2)/(2me)] [-dT^2 + dR^2]
ds^2 = -------------------------------------
(1 + W[(R^2-T^2)/(2me)]) (R^2-T^2)
+ 4m^2 (1 + W[(R^2-T^2)/(2me)])^2 (dU^2 + sin(U)^2 dV^2)
-1/e < (R^2-T^2)/(2me) < infty, 0 < U < pi, -pi < V < pi
Here, the Lambert W function is the holomorphic function defined by
z' = z exp(z) iff z = W(z')
We choose the -principal branch- of the W function, which is real valued
precisely where we need it to be, namely on the interval (-1/e,infty).
At the horizon (the locus R^2=T^2 in the KS chart), it is easy to check
that the line element given just above reduces to
ds^2 = 8m/e [-dT^2 + dR^2] + 4m^2 [dU^2 + sin(U)^2 dV^2]
^^^^^^^^^^^^^^^^^^^^^^^^^^^
where the underlined part is the metric of an ordinary sphere of "radius"
2m. Thus, the K-S chart has no "coordinate singularity" at the event
horizon, contrary to Mitra's claim.
(4) Mitra claims that the Oppenheimer-Snyder collapsing dust ball model
can only yield a black hole with -zero mass-. This is of course absurd;
the OS model is carefully and correctly analyzed in many gtr textbooks,
for example
Hans Stephani,
General Relativity: An Introduction to the Theory of the
Gravitational Field, 2nd ed.
Cambridge University Press, 1990.
In print, ISBN 0-521-37941-5, $39.95 (paperback).
One of Mitra's persistent confusions arises from an apparent inability to
understand the matching employed in building the OS model (in which we
match across the world sheet of a collapsing spherical surface from a dust
ball which is a region of the collapsing FRW dust with E^3 hyperslices, to
a exterior vacuum region, which is a region of the Schwarzschild vacuum).
Mitra also appears to be completely ignorant of the well-known Vaidya null
dust in which a collapsing spherical shell of massless radiation
(Minkowski region vacuum inside the shell, incoherent massless radiation
in the interior of the shell, Schwarzschild vacuum region outside the
shell) collapses from scri^- to form a black hole; see
http://math.ucr.edu/home/baez/RelWWW/history.html
The point is that no matching is required to construct or analyze this
exact solution. The Vaidya null dust is briefly discussed in this review
paper
http://xxx.lanl.gov/abs/gr-qc/0004016
and is also extensively discussed here
http://math.ucr.edu/home/baez/PUB/vaidya
and in the monograph
I. D. Novikov and V. P. Frolov,
Black Hole Physics: Basic Concepts and New Developments,
Kluwer Academic Publishers, 1998
In print, ISBN 0-79-235145-2; list price $98.00 (paperback)
(5) Mitra claims that "the proper time for the formation of any black
hole" (tellingly, he cannot clearly explain what he means by this claim)
is "infinite"; this is also absurd, under any sensible interpretation
(e.g. the proper time measured by an observer riding on the surface of
the OS collapsing dust ball), as every competent student of elementary gtr
knows. This issue is discussed at length in most gtr textbooks; a
particularly well illustrated discussion can be found in
Charles W. Misner, Kip S. Thorne, and John A. Wheeler,
Gravitation,
W. H. Freeman & Company, 1973.
In print, ISBN 0-7167-0344-0; list price $63.95 (paperback).
(6) Mitra claims that the well-known "trapped surface" singularity
theorem is -false-! The (correct) statement and proof can be found in
Robert M. Wald,
General Relativity,
University of Chicago Press, 1984.
In print, ISBN 0-226-87033-2; list price $34.00 (paperback).
Mitra has repeated the claims (1)-(6) in other preprints, and has made
still more incorrect claims, and he has not accepted correction of his
errors:
http://arXiv.org/find/hep-th/1/au:+Mitra_A/0/1/0/all/0/1
> I don't have the stength to go through this paper, but it sounds
> absurd to me:
Of course it is absurd!
> certainly reasonable solutions of the GR equation exist which describe
> gravitation collapse formation of non-charged black-holes. They
> actually claim the later cannot form! Has anyone read this?
In fact, it is only necessary to skim the abstracts of Mitra's preprints
on gtr to see that they all make ludicrous claims which anyone who has
worked through an elementary gtr textbook (e.g Schutz or Stephani) will
know right away are dead wrong.
However, some years ago I read in some detail an earlier draft of
http://arxiv.org/abs/astro-ph/9910408 and it was quite frankly so riddled
with -elementary- misstatements and misconceptions concerning gtr as to be
not only worthless but frankly embarrassing. Mitra is terribly confused
about gtr, and so it is no surprise that it is usually impossible to be
sure exactly what he is trying to say at any given place in this preprint,
because a person who is thoroughly confused in his own mind cannot
possibly express himself clearly! Nonetheless, I believe that anyone who
reads the abstracts of his preprints posted to LANL will see that he
-does- make the claims I listed above.
It is very regrettable that this particular preprint (astro-ph/9910408)
was (shame! shame!) actually -published-:
Found. Phys. Lett. 13 (2000) 543
The irate abstract to an earlier draft of this preprint, unfortunately no
longer available on LANL (but I have a hard copy printout) stated that
Mitra was having a great deal of trouble with the referees; I cannot
understand why the editor apparently decided in the end to publish the
paper with all the misstatements of the original left untouched. The
published version is -shorter- than the original draft but it is no less
-erroneous-.
Chris Hillman
Home Page: http://www.math.washington.edu/~hillman/
--------------------------------------------------------------------------
***ORIGINAL REJOINDER***
------------------------
From: Abhas Mitra, ami...@apsara.barc.ernet.in
Newsgroup: sci.physics.research, sci.physics.relativity
Subject: Rejoinder to Hillman's posting entitled "Black Hole Preprints
by Abhas Mitra"
None of the various posting(s) made by Chris Hillman to this forum [can be
said to be] a scientific critique of my preprints/reprints related to the
non-occurrence of finite (gravitational) mass Schwarzschild Black Holes (BHs),
for the following basic reasons:
(i) It seems that Hillman has not read my papers properly and has attributed
or implied several aspects which are not contained in my papers. Neither has
he made any sincere attempt to understand whatever portions he might have read.
It is possible that he has carefully read only the abstract of these preprints
and subsequently given free rein to his prejudices and predetermined notions.
Some of the comments posted in this forum by others which were lapped up by
Hillman are also likely to have been based [solely] on reading of the abstract.
[For example], as quoted by Hillman, someone [referred to as] "zirkus" wrote,
"I have not looked at the following paper but, according to its abstract...".
(ii) Most of my preprints are based on simple and exact analytical calculations
(WITHOUT ever involving a single assumption or simplification) and associated
equations. A meaningful critique of such works must point out the definitive
errors/shortcomings in specific equations, quoting specific equation numbers.
If there is a conceptual error, a meaningful critique must point out which
specific equation is based on those conceptual errors, or else provide an
interpretation of which equations have been [derived or used] incorrectly.
But as one can see, Hillman has been unable to point out any such specific
error. His comments are either vague or misplaced (by reason of not having
read my preprints carefully). In general, his style of criticism is
non-academic, non-professional, and non-collegial. On the other hand, his
critique, which is meant to be of a purely scientific nature, is actually
filled with personal attack, calumny, derision and intolerance. He has
probably [resorted to] this style because he is apparently incapable of posting
his critique to refereed journals, and he may actually be [resorting to] this
style [out of necessity] to hide and make up for the absence of objective
scientific content.
(iii) In the following, I shall show that whatever little analytical elements
(non-numbered equations) there [happen to be] in the present critique by
Hillman, actually CORROBORATE the results of my preprints!
1. One of my previous preprints (gr-qc/9807197) tried to show that:
If we follow the radial geodesic of a test particle around a BH using any
coordinate system including Lemaitre coordinates (r, t, t=comoving time),
the geodesic, which must be TIMELIKE (ds^2 >0) at any non-singular region
of spacetime, would become null (ds^2=0) at the Event Horizon (EH) at
R=R_g=2M. Hillman asserts that my derivation to this effect is incorrect
because "Part of Mitra's confusion throughout his preprints rest upon
persistent failure to distinguish clearly between coordinate slopes and
physical velocity...".
While he makes this accusation, note that he has NOT pointed out which
EQUATION is based on such "confusion" and in turn, which specific result
is incorrect because of such "confusion". To hide his inability to actually
pinpoint the specific location of error or "confusion" he has unnecessarily
introduced grandiose-sounding mathematical jargon, [i.e. the] "Painleve chart",
and claims, WITHOUT ACTUALLY SHOWING IT, how the "PainleveChar"' disproves
my result. However, his writing makes the pretention that he has actually
disproved my result. For the benefit of the serious readers, I give below
the essence of my proof:
In Lemaitre coordinates, the radial geodesic (angular part=0), the metric
of a test particle around a BH is
ds^2 = dt^2 - g_rr dr^2 (1)
where
g_rr = [(3/2R_g) (r-t)]^{-2/3} (2)
The invariant circumference coordinate R is related to r, t in the following
way:
R = [(3/2R_g) (r-t)]^{2/3} R_g (3)
Thus at R=R_g (2M),
[(3/2R_g)(r-t)]^{2/3} = 1 (4)
Using Eq.(4) in Eq.(2), we find that,
g_rr = 1 at R = R_g (5)
Using Eq.(5) in Eq.(1), we have
ds^2 = dt^2 - dr^2 at R=R_g (6)
Note that while he uses the symbol "r" for circumference coordinate, I am
using "R" for the same; also while Hillman uses "m" for the gravitational
mass of the BH, I use "M" for the same.
We would require here a standard result:
dR -(1-2M/R)
--- = ---------- [E^2 -(1-2M/R)]^{1/2} (7)
dT E
where E is the conserved energy per unit rest mass of the test particle.
Since t is the comoving time, we have
dt = (1-2M/R)^{1/2} dT (8)
Now by using the above equations, it can be found that,
(dr/dt)^2 = 1 at R = R_g (9)
Hillman also writes that "it is true that the coordinate slope equals to
-1 here"; by 'here' he means at R=2M. To verify the correctness of
Eq.(9), however, it would be better to see the Eq. 3.12.5, pp. 112 of
Zeldovich and Novikov, Rel. Astrophysics, Vol. 1, Univ of Chicago (1971):
(dr/dt) = +/- (R_g/R)^{1/2} (3.12.5) of ZN
Note that the tau of ZN is our t, r of ZN is our R and vice-versa, and
recall that we have taken c=G=1.
By putting Eq.(9) in Eq.(6) one can find that INDEED
ds^2 = 0 at R=R_g=2M following the radial geodesic. (10)
If the EH R=R_g were a mere coordinate singularity and actually a regular
region of spacetime, GTR demands that the geodesic must remain timelike
there and we should have had ds^2 > 0. Thus Eq.(10) implies that the
R=2M is NOT a non-singular region of spacetime. [Rather], it corresponds
to a true physical singularity. But, for a BH, we know that the true
physical singularity is at R=0. Therefore we can reconcile Eq.(10) with
this knowledge by recognizing that we must have
R = R_g = 2M = 0 (11)
In other words, the mass of the BH must be
M = 0 (12)
Does this proof ever involve the acusations levelled by Hillman? Did we
ever mention "physical velocity" in this proof? Or did we [suffer from]
any "confusion" between "coordinate slope" and "physical velocity"? Thus
all that Hillman writes in the guise of a critique is actually gibberish.
But to hide the gibberish, he strews some unnecessary mathematical and
geometrical jargon around in his postings about my work.
2. In Sec 3 of his posting, Hillman writes that "Mitra claims that the
Kruskal-Szekers chart has a coordinate singularity at R = 2M; this absurd
(and very incorrect) conclusion..."
Now the fact is that, I HAVE NEVER EVER MADE SUCH A CLAIM IN ANY OF MY
PREPRINTS. This again clearly shows that Hillman has not even cared to
read my papers carefully before ridiculing them by abusing the internet.
On the other hand, I have pointed out, in several of my preprints, that
even if one uses the Kruskal coordinates u and v, one would find that the
EH is a true physical singularity. In other words, I have derived
Eq.(10) using [these] coordinates. In fact, I have done so in a most
straightforward manner using Schwarzschild coordinates too. For the
benefit of the serious readers, I shall, again, give below the essence of
my proof that (du/dv)^2 =1 at R=2M in this regard:
In one of his earlier postings [webpages?] entitled "Hall of Shame'',
Hillman had ridiculed my work purely on the basis of prejudice without
even attempting to put up any scientific critique. All that he could say
was to mention a preprint, (astro-ph/9905144), by I. Tereno which had
scientifically, albeit erroneously, criticised my preprint. Nevertheless,
here Hillman had conveniently forgotten to mention any of my REBUTTALs to
Tereno's work:
A. Mitra, astro-ph/9904163 and 9905329
Anyway let me proceed with my proof:
From Eq.(7), it follows that, dR/dT =0 at R=R_g=2M. And since dT is an
infinitesimal quantity by definition (not to be confused with delta T,
which could be finite or even infinite), we have
dR = 0 at R=R_g=2M along a radial geodesic (13)
The Kruskal coordinates obey, everywhere in the Kruskal diagram, the
equation
u^2 - v^2 = (R/2M -1) exp (R/2M) (14)
so that,
u^2 = v^2, (v/u)^2 = 1 at R=2M (15)
Now differetiating Eq.(14) w.r.t. R, and using Eq.(13) on the LHS, it
follows that
u du - v dv = 0 at R=2M (16)
Or,
(du/dv)^2 = (v/u)^2 at R=2M (17)
Invoking Eq.(15) in Eq.(17), we see that
du^2 = dv^2 at R=2M (18)
Now for a radial geodesic, it can be seen that the Kruskal metric at
R=2M is:
ds^2 = (16M^2/e) (du^2 - dv^2) (19)
Invoke Eq.(18) here and obtain
ds^2 = 0 at R=2M along a radial geodesic (20)
Again note that this proof neither involved any mention of "physical
velocity'' or any associated "confusion". On the other hand any
unbiased reader can see who is actually confused. Rather than finding
any real error in my derivation, in his characteristic way, Hillman
has unnecessarily and irrelevantly invoked grandiose-sounding
"Lambert W function" without showing how the W function or any other
function would actually disprove my Eqs. 13-20. Here Hillman has used
two variables "R" and "T" without even mentioning what they are (note
that I use R and T for Sch. coordinates); presumably they are
proportional to our u and v. For the radial part of the metric,
Hillman too finds, through a convoluted route using the "Lambert W
function" that at the EH
ds^2 = (8m/e) (-dT^2 + d R^2) , R and T not defined by Hillman.
By comparing with Eq.(19), it seems that R= 2m u and T =2m v (at least
at the horizon). Then, we would have (dR/dT)^2 =1 at the EH, and
Hillman's Eq. too would give ds^2=0 at the EH. As explained earlier,
this would mean that the mass of the BH, M=0.
3. Since Hillman has been unable to point out any real error in any of
my preprints, he goes on citing one standard book after another (without
showing how those books actually negate my precise derivations) to
justify his prejudice and calumny. If at any given point of time, the
existing scientific literature and interpretation of laws of Nature were
the ultimate without leaving scope for new analysis and interpretations,
there would not have been any scientific or intellectual progress, and,
intellectually, we would have continued to be like the prehistoric
cavemen.
My crticism of the Oppenheimer-Snyder paper is based on the fact Eq.(36)
of it overlooked the fact that the ARGUMENT OF A LOG FUNCTION CANNOT BE
NEGATIVE. This statement cannot be negated by citing books and pouring
forth ridicules. And this statement demands that during the collapse of
the dust-ball, we must have
2M/R < = 1 (21)
This mathematical result means that TRAPPED SURFACES DO NOT FORM in the
O-S dust collapse. As I have shown (astro-ph/9904163, 9910408), unless
Eq.(21) is incorporated into the O-S analysis, the behaviour of the
metric coefficients would be inconsistent and unphysical at R=0. No
amount of jargon, hand waiving, or personal vilification can undo
Eq.(21).
Here Hillman makes mention of the "Vaidya null-dust" without knowing
that Prof. P.C. Vaidya himself has found my work to be completely
correct.
4. Hillman writes that "Mitra claims that the well-known 'trapped
surface' singularity theorem is false! The correct statement and proof
can be found in.."
Firstly, I never mentioned "trapped surfaces" as singularities.
[Secondly,] it appears that Hillman is unaware of the fact that the
well-known singularity theorems are based on several ASSUMPTIONS. The
most crucial assumption here is that there is a "trapped surface" in
the spacetime. Now when, by definition, existence of "trapped surfaces"
is an ASSUMPTION how can any book PROVE the existence of trapped
surfaces?
On the other hand, I have actually proved, in a general manner, for
spherical collapse of baryonic matter, that trapped surfaces do not form
at all. In other words, I have shown that the crucial assumption behind
the singularity theorems is incorrect (for collapse of isolated bodies).
And since the essence of my proof is so straightforward, for the
seriousreaders, I present it below:
All spherical collapse involving baryonic matter and radiation obey (see
ref. in my paper) a relation
Gamma^2 = 1 + U^2 - 2M/R (22)
where
Gamma = dR/dl (23)
and dl is an element of proper length along the radial worldline of the
collapsing fluid. Also,
U = dR/d tau (24)
where d tau is an element of proper time following the fluid element.
Clearly, Eqs.(23) and (24) are correlated as
U = Gamma V (25)
where
V = dl/d tau (26)
and let us treat V as a pure symbol.
By putting Eq.(25) in Eq.(22) and by transposing, we have
Gamma^2 (1- V^2) = 1 - 2M/R (27)
Now by using the result that the determinant involving the metric coeff.
of any metric must be negative, I have shown that, if (1-V^2) is negative,
then so must be Gamma^2, so that the LHS of Eq.(27) is always positive.
Then it follows that
2M/R < = 1 (28)
a result obtained independently from the O-S work. Eq.(28) shows that, if
the fluid [were to] collapse to a singularity at R=0, under positivity of
mass, one must have
M-->0 as R-->0 (29)
5. The preprint astro-ph/9910408 was published in Foundation of Physics
Letters and this has obviously greatly disappointed Hillman and his ilk.
Why do not they submit an academic critique of my paper to Foundations or
any other standard refereed journal? If they are so sure that it is all
wrong, what prohibits from doing so? Why do they have to express their
disappointment only through such fora [as this one]?
This paper was published in Foundations after several referees failed to
point out any specific errors in my work, after some referees found that
the work is "mathematically" correct, and eventually after two anonymous
referees recommended its publication with some revisions. If this is a
"very regrettable" and "shame shame" procedure, what about Hillman's
gibberish which either distorts my work or contains no real scientific
criticism at all?
6. Hillman's posting started with criticism of my work hep-th/9905182.
In this work I never claimed that non-extremal BHs with mass M>Q (charge)
are not exact GTR solutions, as implied by Hillman. In fact they are as
exact solutions as the Schwarzschild BHs. But if one starts with a M>Q
case and slowly reduces Q to Q=0, one should recover the Sch. BH. In such
a case, one would obtain a finite mass M>0 BH. But since I have already
shown, by several independent modes, that the only allowed value of M is
0, eventually, it is [only] the extremal BHs with M=Q solutions which are
to be accepted because they lead to the correct result M=0 when Q=0.
I invite Hillman and all other readers to write a proper scientific
critique pointing out specific errors in my equations and interpretations
in case any of them think that my work is erroneous. Incidentally, through
email, I have repeatedly requested Profs. S. Hawking. R. Penrose, K.Thorne,
C.W. Misner and many others to send their critique, if any, to me. But none
of them have acted so far. But Hillman has trodden in...
--
Posted from berkleysquare-2.dsl1.easynet.co.uk [217.204.233.98]
via Mailgate.ORG Server - http://www.Mailgate.ORG
dave orton
what seems to be the problem?, book sales even worse than your bible sales were?
alarmism is goin outta style kiddies. copublish my stuff and make money again.
dave orton
"Sabbir Rahman" <intuit...@yahoo.com> wrote in message news:<2463c4a5587b36feb41...@mygate.mailgate.org>...
Uncle Al
>
> Dear Friend and Colleagues,
>
> It is with some disappointment and reluctance that I am forwarding
> this message to the sci.physics and sci.physics.relativity newsgroups,
> which are unmoderated. I hope, nevertheless, that it will be given due
> consideration by those readers of this newsgroup who are open-minded
> and sincere enough to seek scientific truths even if they seem to go
> against their mathematical or physical "intuition".
>
> On 19th July, 2001, a rather scathing attack was made by Chris Hillman
> on the work of Abhas Mitra, regarding the formation and existence of
> black holes (or rather, lack thereof). This is still available on the
> sci.physics.research archives:
>
> http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
>
> Note that the tone used in this email is quite intolerant and
> undignified, being full of personal attack and "flames" and is
> clearly quite contrary to the charter of the sci.physics.research
> newsgroup. Nevertheless, the moderators of the sci.physics.research
> newsgroup (John Baez and Matt McIrvin) accepted Hillman's posting for
> distribution. Note that John Baez is currently hosting Hillman's
> relativity website, so one can safely presume that the three of them
> know each other fairly well.
If Chris Hillman disassembled the critter because his mathmatics was
flawed - so flawed that Hillman was outraged - I suggest you address
the flaws before you criticize the messenger. If Chris Hlllman says
you are full of it, at least one of you has much to gain with a
private dialog. Why do you insist upon making a protracted public
spectacle of a subtle technical dialogue?
Not the hot death thrown at Bernhard Haisch and his SED origination of
inertia - and made to stick. sci.physics.research does not tolerate
flawed analysis.
> I made Abhas Mitra aware of Hillman's posting, and he prepared a
> detailed rejoinder to it, including mathematical details, which I
> forwarded to the newsgroup. This rejoinder was rejected by the
> moderator, Matt McIrvin, on the basis that it contained "personal
> attacks" against Chris Hillman. This of course was surprising, as
> (i) Mitra's rejoinder was a completely justified and direct response
> to Hillman's abusive posting, and (ii) was much tamer in content
> besides, with logical mathematical arguments being presented to show
> the mathematical misconceptions in Hillman's original posting.
Cut the crap. Stop whining. Uncle Al posts to sci.physics.research.
The very heterodox
http://www.mazepath.com/uncleal/eotvos.htm
is not only tolerated, no substantive criticism has ever been
mounted. Given its gainsaying of all metric theories of gravitation,
I'd say your claims of moderator snit and derision are empirically
unfounded. The chiral Etovos experiment is a much fatter and more
succulent target - and much more dangerous to the very foundations of
physics. (How much fun can there be in 75 Kb? Lots!)
You posted 1091 lines. If you know what you are talking about you can
give a good overview using a cocktail napkin and a swizzle stick.
Watch me do it with the heretical chiral Eotvos experiment:
1) The Equivalence Principle says all masses fall identically,
inertial and gravitational masses being indistinguishable in
principle.
2) People have contrasted falling test masses based upon
compositional arguments for more than 400 years, now accurate to
differential one in 10^13 (one milligram in ten thousand metric
tonnes). All experiments null wthin experimental uncertainty.
3) Does anything remain? The best minds in physics have abundantly
applied themselves to the challenge.
4) Your left and right hands are geometrically incommensurable.
They lack a point, plane, and S4 axis of symmetry. They are chiral,
handed, asymmetric, dysymmetric... Nobody has ever considered symmetry
as a test of the Equivalence Principle. Physics doesn't even have the
vocabulary to talk about it.
5) Chemistry has vast databases of chiral crystal structures, we can
qualitatively measure chirality (Mike Glazer), and we can also
quantitate (ab initio via Michel Petitjean and semi-empriical via
David Avnir) crystal lattice geometric chirality.
6) Will mirror image intensely chiral single crystal (no waffle
room!) test massees fall identically to one in 10^13 in geometric
spacetime? Uncle Al gives two scholarly literature references that
explicitly require THEY WILL **MEASURABLY** VIOLATE THE EQUIVALENCE
PRINCIPLE IN EXISTING EOTVOS EQUIPMENT. No physicist dare look lest
he be called out for listening to a chemist.
I've just killed Einstein with an SOP lab experiment, and it didn't
require 1091 lines to do it. 3% of 1091 was more than enough. Now,
go convince Eric Adelberger, Wei-Tou Ni, Riley Newman, or Ramanath
Cowsik to run the experiment in an Eotvos balance.
And stop whining. Scientists don't whine; they conquer or are
defeated.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URLs! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!
Vertner Vergon
"Uncle Al" <Uncl...@hate.spam.net> wrote in message
news:3BB4A856...@hate.spam.net...
>*************************************************************
Vergon:
John Baez & Co. are the Newsgroup equivalent of the Taliban, i.e.,
religious extremist dictators restricting the rights of others, and
who practice a narrow interpretation that they impose on others.
Nor do they tolerate criticism.
They do not know the meaning of research, and are a ball and chain
around the neck of scientific research.
*********************************************************************
Jeremy Price
these boards Vergon!
-Jeremy
Michael Varney
"Vertner Vergon" <VVe...@prodigy.net> wrote in message
news:Es2t7.47577$mU5.3373214972@newssvr15.news.prodigy.com...
>
>
> "Uncle Al" <Uncl...@hate.spam.net> wrote in message
> news:3BB4A856...@hate.spam.net...
> > Sabbir Rahman wrote:
> > >
> Vergon:
>
> John Baez & Co. are the Newsgroup equivalent of the Taliban, i.e.,
> religious extremist dictators restricting the rights of others, and
> who practice a narrow interpretation that they impose on others.
> Nor do they tolerate criticism.
>
> They do not know the meaning of research, and are a ball and chain
> around the neck of scientific research.
Twit.
Vertner Vergon
news:Jx3t7.49671$QK.34...@news1.sttln1.wa.home.com...
*
Vergon:
:-) Another member of the Newsgroup Taliban is heard from.
Take your own advice, Sahib.
Vertner Vergon
news:9p2i27$a76$1...@peabody.colorado.edu...
Vergon:
Yes, they are that too.
Et tu Brutus?
>
Daryl McCullough
(ignoring angular part, for simplicity):
ds^2 = (1 - 2GM/r) dt^2 - (1 - 2GM/r)^{-1} dr^2
What then, is the equation for the path of a radially infalling
observer (no angular momentum)? Well, we can use the fact that
proper time is maximized on a geodesic. Thus r(t) is that function
that maximizes the integral
Integral of square-root((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2) dt
At this point, we can do the following trick: treat the integrand
as a weird kind of Lagrangian, and find the corresponding Hamiltonian
(which will represent a kind of "energy" which is conserved). The
Hamiltonian H is related to the Lagrangian L via:
H = p (dr/dt) - L
where the "momentum" p is defined by p = dL/d(dr/dt).
Using L = square-root((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2)
we find that p = - (1 - 2GM/r)^{-1} (dr/dt)/L. Thus H is given
by
H = p (dr/dt) - L
= - (1 - 2GM/r)^{-1} (dr/dt)^2/L - L
= [- (1 - 2GM/r)^{-1} (dr/dt)^2 - L^2]/L
= [- (1 - 2GM/r)^{-1} (dr/dt)^2
- ((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2)]/L
= - (1 - 2GM/r)/L
= - (1 - 2GM/r)/square-root((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2)
Let's simplify this by considering an observer dropping from rest
(dr/dt = 0) at a distance very far from the Black Hole (so that
2GM/r is approximately zero). In this case, H simplifies to
H = -1
Since H is a constant, it will continue to equal -1 even as
the observer accelerates towards the Black Hole. So we can
solve for dr/dt as follows:
-1 = - (1 - 2GM/r)/square-root((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2)
which implies that
1 - 2GM/r = square-root((1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2)
Squaring both sides gives
(1 - 2GM/r)^2 = (1 - 2GM/r) - (1 - 2GM/r)^{-1} (dr/dt)^2
Multiplying both sides by (1 - 2GM/r) gives
(1 - 2GM/r)^3 = (1 - 2GM/r)^2 - (dr/dt)^2
So
(dr/dt)^2 = (1 - 2GM/r)^2 - (1 - 2GM/r)^3
= (1 - 2GM/r)^2 (1 - (1 - 2GM/r))
= 2GM/r (1 - 2GM/r)^2
So, finally we have
dr/dt = (1 - 2GM/r) square-root(2GM/r)
Now, let's go back to the Schwarzschild metric:
ds^2 = (1 - 2GM/r) dt^2 - (1 - 2GM/r)^{-1} dr^2
For an infalling observer falling from rest from far away,
we have dr^2 = 2GM/r (1 - 2GM/r)^2 dt^2. Therefore, the
proper time for this motion is given by
ds^2 = (1 - 2GM/r) dt^2 - (1 - 2GM/r)^{-1} 2GM/r (1 - 2GM/r)^2 dt^2
= 1 - 2GM/r) dt^2 - (1 - 2GM/r) 2GM/r dt^2
= (1 - 2GM/r)^2 dt^2
So, the proper time ds is related to Schwarzschild coordinate time dt by
ds = (1 - 2GM/r) dt
This is such an incredibly simple result, I feel like there's probably
some way to get to it immediately from the Schwarschild metric, but I
don't see how right now.
Anyway, this (I think) is what caused Abhas Mitra to say that
at the event horizon, ds = 0. Because at the event horizon
r = 2GM, the term multiplying dt goes to zero.
However, this doesn't imply that ds = 0, it seems to me. The problem
is that, because the Schwarzschild coordinates are singular at r = 2GM,
t goes to infinity in a finite amount of proper time. So the expression
ds = (1 - 2GM/r) dt
is an indefinite form at GM/r. The first term (1 - 2GM/r)
goes to zero as the geodesic crosses the event horizon, but
the second term dt goes to infinity. You can't evaluate the
product without further analysis.
That further analysis has been done, by switching to different
coordinates, such as Kruskal-Szekeres coordinates, which are
not singular at r = 2GM. The proper time ds then turns out to
be nonzero for crossing from just above the event horizon to
just below the event horizon.
--
Daryl McCullough
CoGenTex, Inc.
Ithaca, NY
ueb
as you described those of Abhas Mitra. Because I have practical
results (no theory !) which contradict several taught opinia.
For example, my results support also Mitra's investigations
about the non-existence of black holes.
Hillman is obviously the Grey Eminence behind sci.physics.research,
and the moderators only puppets. He plays with forged cards in
the scientific discussion. Preferably he likes to make appear
his rival to be stupid by means of quibbles and embezzling
the most important the rival said. If you are interested, I could
mail several articles from sci.physics.relativity demonstrating
that to you or Prof. Mitra directly. If you are interested in
the above mentioned results, see
http://www.markt-2000.de/patent/section2/sc_works.html
Ulrich Bruchholz
Sabbir Rahman
news:h8s2p9...@Muse2.private.de...
I would be very interested in reading those articles. There are
actually quite a few physicists who are aware of Mitra's work
and have checked it thoroughly and found it to be correct. It is
only a matter of time before his work is generally accepted.
Recent papers by D. Leiter et alii which have been published
make reference to Mitra's published work and provide observable
physical evidence supporting his conclusions.
Both myself and Prof Mitra have had personal exchanges with Chris
Hillman, and frankly it has been a complete waste of time. His
arguments are completely irrational, and he answers straightforward
questions with gibberish or obscure and irrelevant mathematical
observations which he most likely does not fully understand
himself. The fanatical defense of "established" misconceptions
which we are seeing is almost pathetic and complete contrary to
the desire for advancement of scientific knowledge and
understanding.
Not to worry. Things are going to change soon. I have plans in
action to set up alternative fora where such narrow-minded, pompous
individuals will simply have no place.
Best wishes,
Sabbir.
--
Posted from host-72-205.dial.in2home.co.uk [212.225.17.205]
dave orton
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Sabbir Rahman
news:9p2ig...@drn.newsguy.com...
> That further analysis has been done, by switching to different
> coordinates, such as Kruskal-Szekeres coordinates, which are
> not singular at r = 2GM. The proper time ds then turns out to
> be nonzero for crossing from just above the event horizon to
> just below the event horizon.
Thanks for the intelligent, coherent analysis. I'll forward your
comments to Prof Mitra for his consideration.
Best wishes,
Sabbir.
--
Posted from host-72-205.dial.in2home.co.uk [212.225.17.205]
Vertner Vergon
--
_______________________________________________________________
Of universal interest
_______________________________________________________________
EVERYBODY LOVES A SWAP MEET
Profitable, Fun & Informal. Buy - Sell - Swap - Trade - Barter *** ANYTHING.
And it's FREE at http://www.TheWeb-X-change.com
"Sabbir Rahman" <intuit...@yahoo.com> wrote in message
news:e0352e1081e809d9bfa...@mygate.mailgate.org...
************************************************************************
Vergon:
I've had my run in with Hillman -- Baez & co.
I just ignore them and let them prattle on in their mutual admiration
society talking the talk of a very narrow minded viewpoint.
Fortunately, the space they use is negligible and expendible --
and they will never amount to much.
*****************************************************************
John Baez
Vertner Vergon <VVe...@prodigy.net> wrote:
>John Baez & Co. are the Newsgroup equivalent of the Taliban, i.e.,
>religious extremist dictators restricting the rights of others, and
>who practice a narrow interpretation that they impose on others.
>Nor do they tolerate criticism.
My spies brought this article to my attention. Be careful, Vergon.
Just because you're paranoid doesn't mean we're not out to get you.
Nemesis
Baez) wrote:
Be careful, Baez. Just because you're a bona fide pompous ass of the
Star Trek Physics academia does not mean the public is not out to get
you. Here is a little quote for you to think about:
"It is up to the citizens of a free society to either
accept the chauvinism of science without contradiction
or to overcome it by the counterforce of public action."
- Paul Feyerabend
So don't think for a minute that you and your band of crackpot buddies
are above public scrutiny. We, the public, don't like to be looked
down on and we certainly don't like to be told that we're too stupid
to realize that we're being taken to the cleaners. We have gotten rid
of condescending priesthood in the past and we will do so again in the
future. One day soon, we'll wake up from our stupor and we'll wipe
that superiority smirk off your faces.
Nemesis
Nasty Little Truth About Spacetime Physics:
http://home1.gte.net/res02khr/crackpots/notorious.htm
Dirk Bruere
It is a quite informal process.
It's late, and I must get to bed.
Dirk
Dirk Bruere
"Sabbir Rahman" <intuit...@yahoo.com> wrote in message
news:e0352e1081e809d9bfa...@mygate.mailgate.org...
>
> action to set up alternative fora where such narrow-minded, pompous
> individuals will simply have no place.
>
Dirk
Matthew Nobes
[snip]
> The moderators of the sci.physics.research website are quite
> clearly guilty of double-standards here. Apparently it is
> fine to publish inflammatory articles so long as they are
> protecting established physical preconceptions - and clearly
> it is fine to censor ideas which would seem to contradict
> these established preconceptions).
Let's assume you are corect, (I don't really think so, but I'll
play along for a bit) the qustion is so what? You act like there
is some duty of the moderators to be ``fair''. This is clearly
false. THEY took the time to set up that group, THEY spend there
free time reading posts, many of which I'm sure they have little
interest in, and they do it all for FREE.
If you have a problem with their policies form your own moderated
group, don't bitch about how a group of unpaid volunteer's aren't
conforming to your idea of what is fair.
> Scientists, and indeed communities of scientists have often made
> mistakes or had serious misconceptions in the past. This human
> attribute is of course not limited purely to science.
As many people have pointed out on this forum in the past, the
idea of the lone researcher, overturning established science, is,
by and large, a myth.
[Mitra's analysis censored out of existence, note that his claim
that there is a physical singularity at the event horizon (R=2M)
is clearly absured (see, for example, the various curvature
invariants)]
--
"Neutral kaons are even more crazy than silly putty"
-G. 't Hooft
Matthew Nobes, c/o Physics Dept. Simon Fraser University, 8888 University
Drive Burnaby, B.C., Canada, http://www.sfu.ca/~manobes
and...@attglobal.net
>
> Dear Friend and Colleagues,
>
> It is with some disappointment and reluctance that I am forwarding
> this message to the sci.physics and sci.physics.relativity newsgroups,
> which are unmoderated. I hope, nevertheless, that it will be given due
> consideration by those readers of this newsgroup who are open-minded
> and sincere enough to seek scientific truths even if they seem to go
> against their mathematical or physical "intuition".
>
> On 19th July, 2001, a rather scathing attack was made by Chris Hillman
> on the work of Abhas Mitra, regarding the formation and existence of
> black holes (or rather, lack thereof). This is still available on the
> sci.physics.research archives:
>
> http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
>
> Note that the tone used in this email is quite intolerant and
> undignified,
Chris Hillman says things about other posters that
are sometimes pretty rough. He stereotypes people
too. BUT, he does know a helluva lot about relativity.
So if he's objecting to your posting, I suspect that
your posting is crap.
Also, there is no academic censorship on sci.physics.research.
It's a moderated newsgroup, so the moderator gets to
turf out postings that he/she feels aren't of interest
to the group. This is not an academic forum.
If you want to publish something in the scientific
literature, then submit it to a peer reviewed journal.
John Anderson
Robert Karl Stonjek
"Daryl McCullough" However, this doesn't imply that ds = 0, it seems to me.
The problem
> is that, because the Schwarzschild coordinates are singular at r = 2GM,
> t goes to infinity in a finite amount of proper time.
RKS: The expression "t goes to infinity in a finite amount of proper time"
can also be said for the proper time of any observer travelling at c. Thus
no proper time can ever pass at c (x=t=0).
The switching of coordinates trick could also be used to allow an object to
be accelerated to the speed of light (by switching coordinates one
'prevents' the required force from rising to infinity and the one can
overcome the very same hurdle of infinite time in any finite proper time).
This coordinate switching trick should be seen for what it is - a trick. It
either applies to light speed in the same way, or does not apply to either.
One can see that any object following the geodesic into a Schwarzschild
radius is reaching c relative to the non-accelerated starting position
mentioned by Daryl, so the applicability of the Kruskal-Szekeres coordinates
should be the same wherever light speed is involved.
Einstein saw the dissenter coming and explicitly disallowed the use of any
tricks to reach c. You can't consider an object at rest and then
accelerated to some velocity close to c, then switch frames to allow the
object to continue on to c. The very idea is ridiculous, absurd, and in
that simple scenario can be seen for what it is. Why do some many people
blindly follow what Einstein would have definitely disallowed had he thought
of it?
Viewed from a much simpler (SR) perspective, one can see that any rod is
shorter at perpendicular to the surface of a massive sphere than when
horizontal. At the Schwarzschild horizon that length has fallen to zero.
It follows that an infinite number of such rods could be stacked end to end
at the horizon, and it would take an infinite amount of time for any rod to
pass over the distance equal to the total length of those rods (zero and
infinite, depending on where you measure from).
Kind Regards,
Robert Karl Stonjek.
PS According to Wheeler and Ciufolini (Gravitation and Inertia P.65-67) an
alternative interpretation of the three dimensional "maximally extended
Schwartzchild metric" is a wormhole (Einstein-Rosen bridge).
Although the Schwarzschild horizon is not a true singularity but just a
coordinate singularity, the relationship between the Schwarzschild horizon
and the speed of light can be seen in the simple escape velocity equation
that gives the escape velocity from a Schwarzschild horizon to be c.
for academic dissent see the following:-
THE INCOMPLETENESS OF KRUSKAL-SZEKERES SPACETIME
RONALD GAUTREAU
Physics Department, New Jersey Institute of Technology Newark, NJ 07102, USA
Novikov has developed a reference system built around times measured by
radially moving geodesic clocks that is equivalent to Kruskal-Szekeres
coordinates. From analysis of the construction of Novikov's reference
system, I give arguments showing that the reference system is not maximally
extended, as is commonly reported in the literature. On both Novikov and
Kruskal-Szekeres spacetime diagrams, the left-hand side, corresponding to
negative values of the spatial coordinate, should not be included when
describing a physical spacetime. In turn, this means we have to rethink
widely-accepted concepts such as black and white holes that arise from the
usual picture of a maximally-extended Kruskal-Szekeres spacetime
http://ejournals.wspc.com.sg/journals/ijmpa/14/1416/0168.html
Recent Publications in General Relativity
The Incompleteness of Kruskal-Szekeres Spacetime
International Journal of Modern Physics A, 14, 2593-2606 (1999). Based on
an Essay of the same name that was awarded Honorable Mention in the 1998
Gravity Research Foundation Competition.
The usual picture of black holes arises in large part from interpretations
interposed on top of spacetime described in terms of Kruskal-Szekeres
coordinates. I give arguments showing that the left-hand side (u < 0) of
Kruskal-Szekeres spacetime diagrams is not physically valid. With the
left-hand side omitted, serious questions can be raised about the usual
concepts of black holes, white holes, wormholes, etc. that arise from
interpretations based upon spacetime described in terms of the standard
"two-sided" picture of Kruskal-Szekeres coordinates.
http://physics.njit.edu/~gautreau/Papers/recent_publications1a.htm
Note
1) the pdf file on the first link can only be dowloaded by subscribers, the
pdf for the second paper CAN be dowloaded by non-subscribers,
2) other papers discussing the 'incompleteness of Kruskal-Szekeres Spacetime
can be found at the above site.
dave orton
you don't have a pilots licence tho!!
ort da sport
Nemesis <Nem...@nospam.com> wrote in message news:<a77art8hgrbamefei...@4ax.com>...
dave orton
physics is not their first love.
nice old math if you can't create your own.
ort da sport
"Vertner Vergon" <VVe...@prodigy.net> wrote in message news:<xc8t7.47826$tB1.342...@newssvr15.news.prodigy.com>...
Aleksandr Timofeev
Dear John Baez
http://groups.google.com/groups?ic=1&q=msgid:Pine.OSF.4.02A.99102...@goedel1.math.washington.edu
Comments
----------------------------------------------------------------
From: Chris Hillman (hil...@math.washington.edu)
Subject: Re: Chris Hillman Boy Genius!
Newsgroups: sci.physics
Date: 1999/10/23
On Sat, 23 Oct 1999, Aleksandr Timofeev wrote:
> Chris Hillman wrote:
> >
> > On Fri, 22 Oct 1999, Aleksandr Timofeev wrote:
> >
> > > What are your judgements?
> >
> > You are a classic crank.
>
> Why do you constantly avoid (discard) reviewing a symmetry
> of input data?
Wait, hold still, a moment, while I implant this new microchip in your
butt.
Now, how wuz that again? Could you repeat? Their people told my
people
they weren't getting the feed in the puzzle palace.
> Policy again?
The -Puzzle Palace-!! The -Anagram Inn-!!!
> I consider experimentally obtained data from the gravitational
> system which is created by a Nature.
Damn it, the left channel just went out again! We spent an awful lot
of
money in order to get this in stereo, Aleksandr, can you just -hold
still-
a moment, while I... there! That didn't hurt a bit, now, did it?
> 1.1. Magic ratios of linear combinations of planetary masses.
Magic?!! How do you know about that! Even -I- am not cleared to know
about that!
[murmur murmur]
Oh, pardon me, that was declassified years ago. You're clear,
Aleskandr,
fire away!
> Here are the most reliable values of the Solar System [1]
> planetary masses that can be experimentally obtained by celestial
> mechanics:
Whats that? The most reliable value obtained by cyberkenetic
mathematics?
Eh?
[murmur murmur]
Oh, celestial mechanics. Oh.
Actually, you know, Aleksandr, I think I might not be following
-quite-
everything you are saying here. I don't quite see the relevance of
celestial mechanics to the subject of our discussion.
> Jupiter MJU or 1 317.735 |(MJU+MSA)/(MUR+MNE) = 12.9959 ~ 13
> Saturn MSA or 2 95.147 | MJU/(MUR+MNE) = 10.0010 ~ 10
> Neptune MNE or 3 17.23 | MSA/(MUR+MNE) = 2.9948 ~ 3
> Uranus MUR or 4 14.54 | (MJU+MSA)/MNE = 23.9630 ~ 24
> Earth MTE or 5 1.000 | MUR/(MTE+MVE) = 8.0110 ~ 8
> Venus MVE or 6 0.815 | (MNE+MUR)/MVE = 38.9816 ~ 39
> Mars MMA or 7 0.108 | (MTE+MVE)/MME = 33.0000 ~ 33
> Mercury MME or 8 0.055 | MVE/(MMA+MME) = 5.0000 ~ 5
And those are the telemetry settings? The ones you'll give to the
Chinese
if we don't pay you...
> The difference between computed values of ratios and the closest
> integer can possibly be explained by an effect similar (Francis Aston
> 1920) to mass modification caused by dense packing in atom nucleii.
Wait, slow down, you're going too fast for me! My people tell me
their
people can't hear a thing on -either- channel now! Can you stop
dancing
around like that, Aleksandr? You must be interfering with the
satellite
uplink somehow.
> When organised graphically, the ratios [2] of linear combinations
> of the planetary masses considered, reveal a chain of gravitational
> correlations between triples of planets possessing chiral symmetry:
Whoa! Can you break you that down for me in dollars, please?
> 10
> I<----------->|
> I 13 |
> I<==============>I
> I | I
> ? 39 I | I
> |<----------------->I 33 |<---------------->I 24 | I
> | |<------------------>I |<----------------->I
> | | I ? | | I 5 | | I 8 | | I 3 | | I
> | | I<====>| | I<====>| | I<====>| | I<====>| | I
> | | I | | I | | I | | I | | I
> 10 9 I 8 7 I 6 5 I 4 3 I 2 1 I
> I | | I | | I | | I | | I
> I Mercury MarsI Venus EarthI Uran NepI Saturn JupiterI
> I I I I I
> 10+9 8+7 6+5 4+3 2+1
> ln(mass)
And that's the plans for the... oh my gosh! Their people are telling
my
people that does indeed look to be the plans for... Oh my gosh!
Aleksandr,
can you give us some time to react here? Before selling this to the
Chinese? I mean, this a -major- development. An unexpected
development,
to be perfectly frank. Oh, sorry, wrong word. But, Aleksandr, put
yourself where I sit! Secret funds have to transferred, budgets
shuffled,
heads rolled. You have to give us some time! Time! That's all I'm
asking
for Aleksandr, a little time!
> MSA + MJU <-> 2 + 1; MUR + MNE <-> 4 + 3;
> MVE + MTE <-> 6 + 5; MME + MMA <-> 8 + 7;
> MJU <-> 1; MSA <-> 2; MNE <-> 3; MUR <-> 4;
> MTE <-> 5; MVE <-> 6; MMA <-> 7; MME <-> 8;
Shshsh!!! I'm convinced!
[whisper]
You -DO- know the formula for Kentucky Fried Chicken!
> 33+5=6^2+2 39+8=7^2-2 24+3=5^2+2 10+13=5^2-2
>
> +2 -2 +2 -2
And this the code by which our people will contact your people, right?
When we have collected a ransom in the amount of--- how much was that
amount in dollars again, Aleksandr? Put down that glass for a moment,
Aleksandr. This is very important, and we wouldn't want to make a
mistake. We don't there to be any misunderstanding, now, do we? No,
no
more vodka, not right this moment. How much was -that ransom- again?!
> (value of reverse correlation)+(value of direct correlation)=n^2 +/- 2
I'm told they are having a -very- hard time hearing you, Aleksandr.
We
don't seem to be getting more than one channel at a time. Would you
-please- stop--- yes, yes, I know this how you do the Cossack Sailor
Dance, but could you -please- sit down? You are really screwing up the
uplink when you dance around like that!
> There are:
>
> only words; only words; ... ; only words
Oh my God! Washington! Call am ambulance!! I think he's going into
cardiac arrest! What?!! I KNOW he's in Russia! What?!! Oh... Well,
what the heck am -I- supposed to do about that now!? Your people
never
mentioned ANYTHING about "roofing material" to our people before right
this moment!
> Where are there clear proofs instead of a political wandering of words?
What? Just a second, I think he's trying to speak. What was that
Aleksandr? Your last words?
> The reason for this is not alien ideology, but plain and simple narrow
> mindedness brought about by hyper-specialization in all fields of
> sciences.
I think he's gone, Washington. What?! Gone! DEPARTED! He's GIVEN
UP
the GHOST! What?!! That's what I'm trying to TELL you! I -KNOW- you
aren't getting either damn channel now!! I'm trying to TELL you!
It's
ALL OVER! Kaput! FINITO! The Chinese are going to get the Kentucky
Fried Chicken Franchise!!! Are you hearing?!-- oh, bother. I think
we
just lost the downlink too.
Chris Hillman
Home Page: http://www.math.washington.edu/~hillman/personal.html
------------------------------------------------------------------------
Sabbir Rahman
news:Pine.GSO.4.30.010928...@fraser.sfu.ca...
> Let's assume you are corect, (I don't really think so, but I'll
> play along for a bit) the qustion is so what?
> [snip]
If Mitra is correct, it means that the scientific establishment
has misunderstood GTR for at least the last seventy years or so.
Severable notable personalities have built careers (and published
many popular books) based upon these misconceptions, and have
unwittingly been deceiving not only themselves but also the
general public all this time. If nothing else, it would be quite
an embarassment for the scientific establishment, particularly as
so many naive followers believe in and defend outpourings of the
establishment with such fervent religious fanaticism.
The modern-day scientific method is simplistic, narrow-minded,
fallible and a great hindrance to scientific advancement - as
indeed are many of the scientists who so ardently put their
faith in it. It is high time we recognised these problems and
made some concerted efforts to fix it.
Best wishes,
Sabbir.
--
Posted from host-71-12.dial.in2home.co.uk [212.225.16.12]
Matthew Nobes
> "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> news:Pine.GSO.4.30.010928...@fraser.sfu.ca...
>
> > Let's assume you are corect, (I don't really think so, but I'll
> > play along for a bit) the qustion is so what?
> > [snip]
You are quoting me out of context. I was refering to the fact
that the moderators of sci.physics.research are under no
obligation to accept his post in any case.
It is tremedously hypocritcal of you to accuse others of academic
misconduct, while doing it yourself. Please quote me in context
next time.
> If Mitra is correct, it means that the scientific
> establishment has misunderstood GTR for at least the last
> seventy years or so.
I know where my money is.
Seriously, he seems to be claiming that there is a curvature
singularity at R=2M. This is nonsense (the curvature invariants
are finite there). I've done the calculation myself (as have
thousands of grad students).
Like I said, the myth of the lone researcher overturning the
``establishment'' is just that, a myth.
> Severable notable personalities have built careers (and
> published many popular books) based upon these
> misconceptions, and have unwittingly been deceiving not only
> themselves but also the general public all this time. If
> nothing else, it would be quite an embarassment for the
> scientific establishment, particularly as so many naive
> followers believe in and defend outpourings of the
> establishment with such fervent religious fanaticism.
Ahh yes the comparison to religion. Might I humbley suggest you
don't know what you are talking about.
> The modern-day scientific method is simplistic, narrow-minded,
> fallible and a great hindrance to scientific advancement
Shame on us modern scientists for agreeing with so many
experiments!
Apart from ``fallible'' I disagree completely with your
statement. Modern physics has produced agreement between theory
and experiment to absolutly astonishing levels.
How do you define ``scientific advancement''?
> - as indeed are many of the scientists who so ardently put
> their faith in it. It is high time we recognised these
> problems and made some concerted efforts to fix it.
You have a proposal that would make the scientific method
infallible? I'm all ears.
franz heymann
> "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> news:Pine.GSO.4.30.010928...@fraser.sfu.ca...
>
> > Let's assume you are corect, (I don't really think so, but I'll
> > play along for a bit) the qustion is so what?
> > [snip]
>
> If Mitra is correct, it means that the scientific establishment
> has misunderstood GTR for at least the last seventy years or so.
> Severable notable personalities have built careers (and published
> many popular books) based upon these misconceptions, and have
> unwittingly been deceiving not only themselves but also the
> general public all this time. If nothing else, it would be quite
> an embarassment for the scientific establishment,
The physics community thrives on embarrassment. That it the usual way
in which progress is made in the field. *But* the cause of the
embarrassment has to stand up to inspection in the light of day. My
impression is that the present case which you espouse does not do so.
> particularly as
> so many naive followers believe in and defend outpourings of the
> establishment with such fervent religious fanaticism.
>
> The modern-day scientific method is simplistic, narrow-minded,
> fallible and a great hindrance to scientific advancement - as
> indeed are many of the scientists who so ardently put their
> faith in it. It is high time we recognised these problems and
> made some concerted efforts to fix it.
>
> Best wishes,
>
> Sabbir.
Franz Heymann
Daryl McCullough
>Seriously, he [Mitra] seems to be claiming that there is a curvature
>singularity at R=2M. This is nonsense (the curvature invariants
>are finite there).
No, not really. He's claiming that something weirder happens---that
a timelike geodesic becomes lightlike there. (Does that imply a
curvature singularity?)
The issue is that near R=2M, the proper time for a radially infalling
test particle is given by
ds = (1-2M/r) dt
So, as r --> 2M, ds --> 0. Mitra interprets this as meaning that
the geoedesic becomes lightlike (ds^2 = 0).
The problem is that ds^2 is a measure of the separation between
events. If the events coincide, then of course ds^2 will be zero.
With the Schwarzschild coordinates, the points (r=2M, t1)
and (r=2M, t2) are *not* different spacetime events. In
Kruskal-Szekeres coordinates, they are given the same coordinates:
(r_K = 0, t_K = 0). So the fact that ds/dt --> 0 near the horizon
is simply a reflection of the fact that on the horizon, different
time labels describe the *same* event (so of course the separation
between them is zero).
I think that's what's going on.
Matthew Nobes
> Matthew Nobes says...
>
> >Seriously, he [Mitra] seems to be claiming that there is a curvature
> >singularity at R=2M. This is nonsense (the curvature invariants
> >are finite there).
>
> No, not really. He's claiming that something weirder happens---that
> a timelike geodesic becomes lightlike there. (Does that imply a
> curvature singularity?)
At one point in the long screed that was posted Mitra claims that
there is a ``true physical singularity'' at the ``EH''. To me
that *must* be a curvature singularity, though I suspect Mitra
simply doesn't understand the difference.
[snip analysis]
Uncle Al
>
> On 29 Sep 2001, Daryl McCullough wrote:
>
> > Matthew Nobes says...
> "Neutral kaons are even more crazy than silly putty"
> -G. 't Hooft
More than 300 million Silly Putty eggs (4500 tons) have been sold
since the product went on the market in 1950. That is one whole lot
of ruined carpeting.
In 1989 at Alfred University a 100-lb Silly Putty egg was dropped from
the roof of McMahon Engineering Building. The ball bounced about 8
feet into the air, returned to Earth, and shattered on the second
impact.
Dow Corninge 3179 Dilatant Compound (aka "Silly Putty")
-------------------------------------------------------
65% - Dimethyl Siloxane, hydroxy-terminated polymers with boric acid
17% - Silica, quartz crystalline
9% - Thixotrol ST
4% - Polydimethylsiloxane
1% - Decamethyl cyclopentasiloxane
1% - Glycerine
1% - Titanium Dioxide
http://www.sillyputty.com/product_library/prod_library.htm
http://home.earthlink.net/~gschenberg/sillyput.htm
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
Michael Varney
DING Savian, DING!
Martin Gradwell
John Baez <ba...@galaxy.ucr.edu> wrote in message
news:9p34gt$q1s$1...@glue.ucr.edu...
John,
Sabbir Rahman has brought to our attention what appears to
be a very severe case of anti-science bias in the 'moderation'
of sci.physics.research, in that you permit an unprovoked
and intemperate attack on a serious scientist, but you reject
a measured and thoughtful response, one which would allow
people to make up their own minds. I was inclined to make
a strong comment, but I waited because I thought it was only
fair to give you or the other moderators a chance to explain
or apologise. You have had that chance, and you have
thrown it away.
As I said, you don't allow a very moderately worded and
carefully thought out detailed refutation of an immoderate,
insulting and unscientific post. However, you allow such
"rigorous and scientifically sound" arguments as:
-----------------------------------------------------------
>Surely there must be some mathematical errors in this work?
No doubt. There are certainly many in all his previous works.
-----------------------------------------------------------
and
-----------------------------------------------------------
The problem seems to be that Mitra's papers fall into the category of
"not even wrong". When I last looked at one of his papers there was
no matter of finding the point where an error was made and the
calculation deviated from correctness, it was just off from the
get-go.
-----------------------------------------------------------
..not to mention a posting which refers back to Hillman's
original posting as if it is a pinnacle of rationality, and which
points out as a 'flaw' the fact that Mitra doesn't speculate
about "wormhole" black holes which are part of the initial
structure of spacetime from the big bang, or about black
holes which are created entirely by gravitational collapse
of gravitational radiation. (In fact, Mitra doesn't seem to
be into overly speculative flights of fancy at all.)
All of these attacks are allowed, but rational and
moderate self defence making use of scientific arguments
is not.
This is an appalling application of double standards, and
I hope that you realise how appalling it is, but I suspect
that you don't, or that you couldn't care less. If you do
care, the good news is that it still isn't too late for you
to indicate that my suspicions are unfounded.
You presumably still have the text of the posting that has
been sent to you by Sabbir Rahman. If not, it has been
embedded in the post which began this thread.
If you post it in sci.physics.research, even at this late date,
most people will agree that it is better late than never.
Apologies to Sabbir and to Vertner (for the not-so-veiled
threat which was probably intended to be a joke but
which is in extremely poor taste) would probably then be
sufficient to close the incident, without too much damage to
your reputation, and to the reputation of the newsgroup of
which you are a moderator. With more care in the future to
prevent repetition, you could even emerge eventually with an
enhanced reputation.
It is never too late to make a start and make things better.
Please think about it.
Martin Gradwell, mtgra...@btinternet.com
http://www.btinternet.com/~mtgradwell/
James Hunter
Uncle Al wrote:
> Sabbir Rahman wrote:
> >
> > Dear Friend and Colleagues,
> >
> http://www.mazepath.com/uncleal/eotvos.htm
>
> i
>
>
> I've just killed Einstein with an SOP lab experiment, and it didn't
> require 1091 lines to do it. 3% of 1091 was more than enough. Now,
> go convince Eric Adelberger, Wei-Tou Ni, Riley Newman, or Ramanath
> Cowsik to run the experiment in an Eotvos balance.
>
> And stop whining. Scientists don't whine; they conquer or are
> defeated.
It's doesn't really matter that much though what your "scholarly"
discourse
shows though, given that not only wouldn't anybody in engineering
be caught dead listening to a chemist, they wouldn't
be caught alive listening to a physicist.
Aaron Bergman
<e0352e1081e809d9bfa...@mygate.mailgate.org>,
"Sabbir Rahman" <intuit...@yahoo.com> wrote:
> I would be very interested in reading those articles. There are
> actually quite a few physicists who are aware of Mitra's work
> and have checked it thoroughly and found it to be correct.
Most of us just mock him incessantly, however.
It's quite fun.
Aaron
Uncle Al
>
> Uncle Al wrote:
>
> > Sabbir Rahman wrote:
> > >
> > > Dear Friend and Colleagues,
> > >
> > http://www.mazepath.com/uncleal/eotvos.htm
> >
> > require 1091 lines to do it. 3% of 1091 was more than enough. Now,
> > go convince Eric Adelberger, Wei-Tou Ni, Riley Newman, or Ramanath
> > Cowsik to run the experiment in an Eotvos balance.
> >
> > And stop whining. Scientists don't whine; they conquer or are
> > defeated.
>
> It's doesn't really matter that much though what your "scholarly"
> discourse
> shows though, given that not only wouldn't anybody in engineering
> be caught dead listening to a chemist, they wouldn't
> be caught alive listening to a physicist.
OK - No chemist could aspire to the engineering grandeur of Galloping
Gertie or the physics of Hiroshima, Nagasaki,and Kabul. The best we
organikers can do is nylons, Spandex, vinyl plastisol sex toys, and
Viagra. Ya gotta know what is important in life. (Richard Simmons
and Michael Jackson aren't our responsiblity for any of it.)
James Hunter
Uncle Al wrote:
> James Hunter wrote:
> >
> > Uncle Al wrote:
>
> >
> > It's doesn't really matter that much though what your "scholarly"
> > discourse
> > shows though, given that not only wouldn't anybody in engineering
> > be caught dead listening to a chemist, they wouldn't
> > be caught alive listening to a physicist.
>
> OK - No chemist could aspire to the engineering grandeur of Galloping
> Gertie or the physics of Hiroshima, Nagasaki,and Kabul. The best we
> organikers can do is nylons, Spandex, vinyl plastisol sex toys, and
> Viagra. Ya gotta know what is important in life. (Richard Simmons
> and Michael Jackson aren't our responsiblity for any of it.)
We unfortunately engineers have never really cared all much what chemists
aspire to,
given that chemistry is like well *chemisty* and not --robots and
computers--.
Dirk Bruere
>
> In 1989 at Alfred University a 100-lb Silly Putty egg was dropped from
> the roof of McMahon Engineering Building. The ball bounced about 8
> feet into the air, returned to Earth, and shattered on the second
> impact.
Reminds me of a story I heard about how some students decided soak a
lecturers car from about 18 stories up. A few litres in a balloon did the
trick. Quite a big repair bill as well.
Dirk
Sabbir Rahman
> You are quoting me out of context. I was refering to the fact
> that the moderators of sci.physics.research are under no
> obligation to accept his post in any case.
>
> It is tremedously hypocritcal of you to accuse others of academic
> misconduct, while doing it yourself. Please quote me in context
> next time.
>
I apologise for quoting you out of context. It was not my intention
to be "tremendously hypocritical", though I do think there is some
relevance in my response even in the context of the sci.physics.research
newsgroup. If the latter newsgroup does indeed solely exist to satisfy
the egoes of the moderators (which would make it a tremendous waste of
time and space), then your comments seem to be quite valid. However, it
is more likely that sci.physics.research is intended to be a resource
for serious researchers in physics, in which case it has quite an
important role to play as a discussion forum for exchange of ideas, etc.,
in which case my response seems (at least to me) to be quite relevant.
[I do not know the historical raison d'etre of the newsgroup, but as I
understand it, moderated newsgroups such as this are typically created
after a public vote on the basis of a proposition suggesting why the
newsgroup would be valuable, etc. There may even be standard USENET rules
for the procedure, though I am no expert.]
> Like I said, the myth of the lone researcher overturning the
> ``establishment'' is just that, a myth.
There may not be many of them, but they do exist. In my own personal
experience they have also existed in pairs, or even small groups.
Obviously the number of researchers involved increases with time if
the ideas are sound, and the case under discussion is no exception.
> Ahh yes the comparison to religion. Might I humbley suggest you
> don't know what you are talking about.
Well I hope we can agree to disagree on this matter. Science is very
much like a religion to many. The claim that "black holes don't exist"
can be quite analogous to "God doesn't exist", except for the case
that the first may be mathematically decidable in a given theoretical
model.
> Shame on us modern scientists for agreeing with so many
> experiments!
The experiments are usually designed to test particular theories, and
so the interpretations of those results are usually made in the context
of the theories which prompted them. It is rare that other theories
which could have produced the same results are even considered (even
though it would be quite reasonable to do so), and particularly so if
those theories go against what has been acceptably "theorised" to date,
and are therefore "crackpot" theories.
The modern scientific method therefore encourages only incremental
changes of established theories and tends to discriminate against
theories which would produce step changes in understanding. There is a
greater need then to give "crackpot" theories a chance. But why pass
judgment before the theories have been fairly tested? To not test such
theories at all would seem to presume that the answer sought is somehow
already known.
This is not to say that incremental changes are not valuable, or that
step changes do not occur - they are just much rarer than they could be.
> Apart from ``fallible'' I disagree completely with your
> statement. Modern physics has produced agreement between theory
> and experiment to absolutly astonishing levels.
I forgot to mention that a corollary to the above is that the results
of experiments whose results tend to verify "crackpot" theories, or
which invalidate established theories but are suggested by non-established
scientist, tend to be conveniently ignored. (I hope these explanations
clarify to you why I used the adjectives I did).
> How do you define ``scientific advancement''?
That's quite a deep question with no obvious answer. I would recommend
reading Lewis Mumford. He had a very nice perspective on the matter.
> You have a proposal that would make the scientific method
> infallible? I'm all ears.
Not quite, but I do believe that there are better ways to do science.
I can't easily demonstrate this to you now, but patience is a virtue...
Best wishes,
Sabbir.
--
Posted from host-71-176.dial.in2home.co.uk [212.225.16.176]
Matthew Nobes
> "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> news:Pine.GSO.4.30.01092...@fraser.sfu.ca...
>
> > You are quoting me out of context. I was refering to the fact
> > that the moderators of sci.physics.research are under no
> > obligation to accept his post in any case.
> >
> > It is tremedously hypocritcal of you to accuse others of academic
> > misconduct, while doing it yourself. Please quote me in context
> > next time.
> >
>
> I apologise for quoting you out of context. It was not my
> intention to be "tremendously hypocritical", though I do
> think there is some relevance in my response even in the
> context of the sci.physics.research newsgroup. If the latter
> newsgroup does indeed solely exist to satisfy the egoes of
> the moderators (which would make it a tremendous waste of
> time and space), then your comments seem to be quite valid.
> However, it is more likely that sci.physics.research is
> intended to be a resource for serious researchers in physics,
> in which case it has quite an important role to play as a
> discussion forum for exchange of ideas, etc., in which case
> my response seems (at least to me) to be quite relevant.
My point is simple. The group is intended for serious discussion
of physics *as*that*is*construed*by*the*moderators. They get to
make the descisions, as it is they who have accepted the
thankless task of moderating. If you disagree with their
decisions then you are free to create your own group.
> [I do not know the historical raison d'etre of the newsgroup,
It was designed to promote serious physics discussions free of
the crackpot nonsense on the unmoderated groups.
> but as I understand it, moderated newsgroups such as this are
> typically created after a public vote on the basis of a
> proposition suggesting why the newsgroup would be valuable,
> etc. There may even be standard USENET rules for the
> procedure, though I am no expert.]
Sure there are rules for the *creation* of the group. But no
particular rules for moderation. If I wanted to create a
moderated group where the moderation policy was based on the
colour of my shirt that would be fine, so long as I got the
required number of votes (and not even that for the alt groups).
> > Like I said, the myth of the lone researcher overturning the
> > ``establishment'' is just that, a myth.
>
> There may not be many of them, but they do exist. In my own
> personal experience they have also existed in pairs, or even
> small groups. Obviously the number of researchers involved
> increases with time if the ideas are sound, and the case
> under discussion is no exception.
Please. The claims that Mitra is making are refuted hundreds (if
not thousands) of times a year by graduate students takeing GR
classes. His writings (at least those that you posted) reveal
deep misunderstandings of GR.
> > Ahh yes the comparison to religion. Might I humbley suggest you
> > don't know what you are talking about.
>
> Well I hope we can agree to disagree on this matter. Science
> is very much like a religion to many.
I suppose, to those you do not understand it.
> The claim that "black holes don't exist" can be quite
> analogous to "God doesn't exist", except for the case that
> the first may be mathematically decidable in a given
> theoretical model.
Sure, and it has been decieded. Go read Penrose and Hawking
papers of the early seventies. They proved lots of theorems,
which are widely accepted by mathmaticians.
If Mitra is correct where is the flaw in Penrose's proof?
> > Shame on us modern scientists for agreeing with so many
> > experiments!
>
> The experiments are usually designed to test particular
> theories, and so the interpretations of those results are
> usually made in the context of the theories which prompted
> them. It is rare that other theories which could have
> produced the same results are even considered (even though it
> would be quite reasonable to do so), and particularly so if
> those theories go against what has been acceptably
> "theorised" to date, and are therefore "crackpot" theories.
This is outright false in many fields. In GR the PPN formalism
was designed to test many different ``test-theories'' of
gravitation.
Many experiments in particle physics during the early seventies
directly tested to radically different theories of hadron
structure (QCD vs. the S-matrix theory).
> The modern scientific method therefore encourages only
> incremental changes of established theories and tends to
> discriminate against theories which would produce step
> changes in understanding.
Again, modern history of science doesn't bear this out. I would
certainly argue that the standard model of particle physics has
produced a ``deep change'' in understanding.
The entire concept of the renormalization group has profoundly
altered the way that people in many different fields view systems
with a large number of degrees of freedom. Only a fool would
argue that this new perspective is not a profound shift.
> There is a greater need then to give "crackpot" theories a
> chance. But why pass judgment before the theories have been
> fairly tested?
1) in my experiance (and that is fairly consierable) 99% of
``crackpot'' theories don't make testable predictions. The few
``alterante'' theorys that do make them, aren't crackpot at all
(the best example is the work of Ilja Schmelzer).
2) some ``crackpot'' theories have been tested. And found false
(see the SLAC experimetn which disproved autodynamics).
> To not test such theories at all would seem to presume that
> the answer sought is somehow already known.
The answer in most cases *is* known.
There is a vast body of expeirmental data which confirms GR. Add
to that the *PROVEN*FACT* that GR+classical matter nesscessaryly
gives you a singularity and you have a rock solid prediction of
black holes. Not to mention that the things seem to have been
observed.
> This is not to say that incremental changes are not valuable,
> or that step changes do not occur - they are just much rarer
> than they could be.
This largely hinges on what you mean by incremental. But I would
refer to the standard model of particle physics, and the
development of the renormalization group as steep changes.
> > Apart from ``fallible'' I disagree completely with your
> > statement. Modern physics has produced agreement between theory
> > and experiment to absolutly astonishing levels.
>
> I forgot to mention that a corollary to the above is that the
> results of experiments whose results tend to verify
> "crackpot" theories, or which invalidate established theories
> but are suggested by non-established scientist, tend to be
> conveniently ignored. (I hope these explanations clarify to
> you why I used the adjectives I did).
Sure they clarify *why* but I still mainain that your view is
false.
Can you point out one reproducable expeirment that is being
coveniently ignored?
The most obvious experiment that might conflict with GR (Pioneer
staellites) is not being ignored.
> > How do you define ``scientific advancement''?
>
> That's quite a deep question with no obvious answer. I would
> recommend reading Lewis Mumford. He had a very nice
> perspective on the matter.
Nice dodge.
> > You have a proposal that would make the scientific method
> > infallible? I'm all ears.
>
> Not quite, but I do believe that there are better ways to do
> science. I can't easily demonstrate this to you now, but
> patience is a virtue...
When you come up with a theory that reproduces more experimental
results then GR+SM let me know.
Vertner Vergon
.
"Martin Gradwell" <mtgra...@btinternet.com> wrote in message
news:9p5j4e$lcp$1...@plutonium.btinternet.com...
***************************************************************
Vergon:
I see no threat, veiled or otherewise in my statement. However
as to the analogy being in bad taste, it's not half so bad as the
actions of Baez & Co. which not only exhibets bad taste but an
arrogance that goes with it.
I have had my time with them, many times, and have experienced what
you have -- so I speak from experience. And I make no apologies
for the analogy.
*************************************************************************
>
Vertner Vergon
Vergon:
I never took Latin but if that means what I think it means,
all I can say is "Right on!"
Who are the custodians of the custodians?
Or
Who watches the foxes that guard the hen house?
******************************************************************
James Hunter
Vertner Vergon wrote:
> "Uncle Al" <Uncl...@hate.spam.net> wrote in message
> news:3BB65E06...@hate.spam.net...
> > James Hunter wrote:
> > >
>
> > Uncle Al
> > http://www.mazepath.com/uncleal/
> > (Toxic URL! Unsafe for children and most mammals)
> > "Quis custodiet ipsos custodes?" The Net!
> *******************************************************************
> Vergon:
>
> I never took Latin but if that means what I think it means,
> all I can say is "Right on!"
>
> Who are the custodians of the custodians?
>
> Or
>
> Who watches the foxes that guard the hen house?
Nobody does, that's why "scientists" are generally
reminded that they are only slightly less moronic
than philosophers who use Latin and ask
rhetorical questions about hen houses.
Bennett Standeven
> Dear Friend and Colleagues,
>
> It is with some disappointment and reluctance that I am forwarding
> this message to the sci.physics and sci.physics.relativity newsgroups,
> which are unmoderated. I hope, nevertheless, that it will be given due
> consideration by those readers of this newsgroup who are open-minded
> and sincere enough to seek scientific truths even if they seem to go
> against their mathematical or physical "intuition".
>
> On 19th July, 2001, a rather scathing attack was made by Chris Hillman
> on the work of Abhas Mitra, regarding the formation and existence of
> black holes (or rather, lack thereof). This is still available on the
> sci.physics.research archives:
>
> http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
>
> I made Abhas Mitra aware of Hillman's posting, and he prepared a
> detailed rejoinder to it, including mathematical details, which I
> forwarded to the newsgroup. This rejoinder was rejected by the
> moderator, Matt McIrvin, on the basis that it contained "personal
> attacks" against Chris Hillman.
[...]
> Matt McIrvin did suggest that if we sent a version without the personal
> attacks, he would consider it for posting. On this basis I prepared a
> second version (appended below).
[...]
>
> ----------------------------------------------------------------------
>
> From: Abhas Mitra, ami...@apsara.barc.ernet.in
> Newsgroup: sci.physics.research, sci.physics.relativity
>
> Subject: Rejoinder to Hillman's posting entitled "Black Hole Preprints
> by Abhas Mitra"
>
[...]
> My criticism of the Oppenheimer-Snyder paper is based on the fact Eq.(36)
> of it overlooked the fact that the ARGUMENT OF A LOG FUNCTION CANNOT BE
> NEGATIVE. This statement cannot be negated by citing books and pouring
> forth ridicules.
In the spirit of this criticism, I shall comment on Mitra's proof,
from the beginning:
> In Lemaitre coordinates, the radial geodesic (angular part=0), the metric
> of a test particle around a BH is
>
> ds^2 = dt^2 - g_rr dr^2 (1)
Clearly, not a valid equation. Calculus, and hence differential
geometry, are based on the theory of infinitesimals. But this theory
is not logically rigorous, so the rest of your proof is suspect.
>
> where
>
> g_rr = [(3/2R_g) (r-t)]^{-2/3} (2)
>
This equation is invalid, because it overlooks the fact that cube
roots cannot be constructed. Several later equations are also invalid,
for the same reason.
As many of these equations are crucial to the proof, I see no point in
continuing the critique.
(These statements of mine "cannot be negated by citing books and
pouring forth ridicules".)
Joe Fischer
: There is a vast body of expeirmental data which confirms GR. Add
: to that the *PROVEN*FACT* that GR+classical matter nesscessaryly
: gives you a singularity and you have a rock solid prediction of
: black holes.
What is this *PROVEN*FACT* stuff, adding good
experimental prediction history to some assumption
about classical matter and ignoring the fact that
Newtonian attraction is _contrary_ to General Relativity
hardly qualifies as a proven fact.
Stars have a very difficult time forming if
Newtonian attraction or any kind of attraction is used,
and with attraction as the mechanism of congregation,
there is no control over the size of stars, which is
a suggestion that existing ideas about the part of
classical matter theory concerning gravity is not
well know and certainly not proven.
Unfortunately my only reference for now is
not in a journal but in an issue of Air and Space
about 3 or 4 years ago.
If gravity is geometric, then assumptions
about matter pulling itself into a singularity
can be very wrong.
It is more likely that the upper few miles
of even an iron star would not be compressed as
the center is, making a full singularity unlikely.
I admit I am arguing with a bias, as I
see Divergent Matter as a better predictive model
than the mixture of GR and Newtonian attraction,
with many differences from classical matter
and Newtonian attraction.
It looks to me like a dense star is formed
in every "collapse", with the black hole assumption
as being still hypothetical.
A neutron star is extremely hot, yet a black
hole must cool before forming.
There are just too many things about Newtonian
attraction that are contrary to physical mechanisms
in gravitational physics.
And General Relativity is based on a departure
from the Newtonian attraction notion. Black hole
theory would have freefall as being an acceleration,
while General Relativity identifies it as inertial
motion.
: Not to mention that the things seem to have been observed.
High mass concentrations and possibly accretion
discs have been observed, but there are serious problems
with observing small objects, even if they are very'
hot they are much harder to see than cooler large
objects.
Most neutron stars cannot or could not be
seen until radio telescopes identify the existence
of a strong radio source in some kind of cyclic
high energy state, which is the opposite of what
a black hole would be.
Joe Fischer
--
3
David Evens
wrote:
I see that you are unfamiliar with singularities. There is no such
thing as a partial singularity. It either forms or it does not form.
If it forms, all matter in the body colapses into it. It is physiclly
impossible for this not to happen once the singularity forms.
> I admit I am arguing with a bias, as I
>see Divergent Matter as a better predictive model
>than the mixture of GR and Newtonian attraction,
>with many differences from classical matter
>and Newtonian attraction.
I see you are unfamiliar with the post you were rpelyijng to, as well.
There is no mixture of GR and Newtonian gravity involved in that post,
the combinatin is GR and classical matter.
> It looks to me like a dense star is formed
>in every "collapse", with the black hole assumption
>as being still hypothetical.
> A neutron star is extremely hot, yet a black
>hole must cool before forming.
You forgot to support your assumption that a black hole must cool
before forming.
> There are just too many things about Newtonian
>attraction that are contrary to physical mechanisms
>in gravitational physics.
> And General Relativity is based on a departure
>from the Newtonian attraction notion. Black hole
>theory would have freefall as being an acceleration,
>while General Relativity identifies it as inertial
>motion.
You forgot to support your assumption that GR contains this
contradiction.
>: Not to mention that the things seem to have been observed.
>
> High mass concentrations and possibly accretion
>discs have been observed, but there are serious problems
>with observing small objects, even if they are very'
>hot they are much harder to see than cooler large
>objects.
> Most neutron stars cannot or could not be
>seen until radio telescopes identify the existence
>of a strong radio source in some kind of cyclic
>high energy state, which is the opposite of what
>a black hole would be.
Black holes can be quite easy to see, actually. Quasars are black
hole products, and they are the brightest objects in the observable
universe.
-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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Martin Gradwell
> Vergon:
>
> I see no threat, veiled or otherewise in my statement. However
> as to the analogy being in bad taste, it's not half so bad as the
> actions of Baez & Co. which not only exhibets bad taste but an
> arrogance that goes with it.
>
> I have had my time with them, many times, and have experienced what
> you have -- so I speak from experience. And I make no apologies
> for the analogy.
> *************************************************************************
My post, and in particular my suggestion of an apology,
was not addressed to you, but to John Baez.
John Baez wrote:
"My spies brought this article to my attention. Be careful, Vergon.
Just because you're paranoid doesn't mean we're not out to get you."
and it is this that could easily be interpreted as a threat.
You may not see it that way, and you may not think that John
owes you an apology. That's up to you.
Furthermore, I was not suggesting that your analogy was in
bad taste, though it might possibly be interpreted as an insult
to the Taliban. That's OK, though,I can understand why people
might want to insult the Taliban at this time.
Martin Gradwell, mtgra...@btinternet.com
http://www.btinternet.com/~mtgradwell/
--
Posted from host213-122-204-216.btinternet.com [213.122.204.216]
Steve Carlip
> He's claiming that something weirder happens---that
> a timelike geodesic becomes lightlike there. (Does that
> imply a curvature singularity?)
It doesn't imply anything, since it can't happen. Here's a
simple proof: consider a geodesic with affine parameter l,
and tangent vector u^a = dx^a/dl. The quantity
u^2 = g_{ab}u^a u^b
determines whether the geodesic is timelike, lightlike, or
spacelike.
Now consider the derivative of u^2 along the geodesic:
d(u^2)/dl = u^c\partial_c(u^2) = u^c\del_c (u^2)
where \del is the covariant derivative, and the last equality
holds because the covariant derivative of any scalar is the
same as the ordinary partial derivative. Next use the usual
product rule:
d(u^2)/dl
= 2g_{ab}(u^c\del_c u^a)u^b + (\del_c g_{ab})u^a u^b
The second term on the right-hand side vanishes, since the
covariant derivative of the metric is always zero. But the
first term on the right-hand also vanishes: the curve is, by
assumption, an affinely parametrized geodesic, and the geodesic
equation is
u^c\del_c u^a = 0.
So u^2 has vanishing derivative along the curve, and thus
remains constant. A timelike geodesic *can't* become
lightlike, at a black hole horizon or anywhere else.
Steve Carlip
ueb
> Can you point out one reproducable expeirment that is being
> coveniently ignored?
http://www.markt-2000.de/patent/section2/sc_works.html
Ulrich Bruchholz
Sabbir Rahman
> My point is simple. The group is intended for serious discussion
> of physics *as*that*is*construed*by*the*moderators. They get to
> make the descisions, as it is they who have accepted the
> thankless task of moderating. If you disagree with their
> decisions then you are free to create your own group.
Well it would be nice if they were not to have such blatant double
standards in their application of the newsgroup charter to which
they purport to adhere. While they may have the right to do this
on the basis that it is their newsgroup and that they are the
moderators, it certainly doesn't say much for their character or
for their scientific objectivity.
> Please. The claims that Mitra is making are refuted hundreds (if
> not thousands) of times a year by graduate students takeing GR
> classes.
Yes, graduate students can certainly be naive, unassuming and
gullible, which is not surprising given that they believe they are
being handed down knowledge from the world-leading experts in their
fields. I took those classes too, and I think I would be a little
more weary if I were to take them a second time.
> ...His writings (at least those that you posted) reveal
> deep misunderstandings of GR.
...
> > [...] except for the case that
> > the first may be mathematically decidable in a given
> > theoretical model.
>
> Sure, and it has been decieded. Go read Penrose and Hawking
> papers of the early seventies. They proved lots of theorems,
> which are widely accepted by mathmaticians.
>
> If Mitra is correct where is the flaw in Penrose's proof?
Your claims are statements of faith. They do not constitute an objective
scientific analysis of Mitra's work, and in that sense differ little
in content from Hillman's "critique". Where, specifically is the
error in Mitra's work? Clearly you believe Mitra to be a crackpot
purely on the basis of his conclusions, which happen to contradict
your (and others') beliefs.
Mitra has clearly shown the error in Oppenheim & Snyder's work which
originally lead to the proposal of the existence of black holes,
and to date has not failed, on request, to show where others have
made mistakes. To date, no-one has succeeded in finding an error
in Mitra's analysis, which is presumably why his work has eventually
been accepted for publication. And this was certainly not for want of
trying by the many referees of his work.
If you would kindly let me know which proofs of black hole
formation by Penrose and Hawking you are referring to, I will
happily pass them on to Abhas Mitra for his response. And if you
could also let me know which of Penrose's proofs Mitra's work is
contradicting, I will pass that on too. Or would I be correct in
supposing that you have no specific proof in mind, and are merely
appealing to Penrose and Hawking's established reputations as if
this somehow constitutes indisputable evidence for your claims?
[The other things were going off-topic, albeit interesting, so
let's leave those discussions for another day. With the exception
of the following...]
> When you come up with a theory that reproduces more experimental
> results then GR+SM let me know.
I have made some rather nice discoveries regarding the estimation
of Poisson processes which shows quite clearly that statisticians
have been doing it wrong all this time (this work for the time
being remains unpublished). Presumably this has many more real-life
practical applications than either GR or the SM. Indeed many areas
of pure and applied mathematics I am sure have more experimental
relevance than either of these. Besides the standard model possibly
isn't even renormalisable - see the work of Cheng on the hep-th
archives. Again, a discussion for another day, perhaps.
--
Posted from host-72-205.dial.in2home.co.uk [212.225.17.205]
Sabbir Rahman
news:24c3076b.01092...@posting.google.com...
> Clearly, not a valid equation. Calculus, and hence differential
> geometry, are based on the theory of infinitesimals. But this theory
> is not logically rigorous, so the rest of your proof is suspect.
>
> >
> > where
> >
> > g_rr = [(3/2R_g) (r-t)]^{-2/3} (2)
> >
>
> This equation is invalid, because it overlooks the fact that cube
> roots cannot be constructed. Several later equations are also invalid,
> for the same reason.
I actually agree with you. The defeat of Brouwer's intuitionism at the
hands of axiomatic set theory was very sad. Mathematics is derived from
(human) observation and not the other way around. And the physical world
seems to be more in keeping with intuitionism (the recent work of Fotini
Markopoulou et al. on quantum gravity has been quite reassuring in this
regard), than with its more popular, and more dubious, alternative. Maybe
one day we will put mathematics back in its proper place and go back and
do it properly. But given that this would involve overturning quite a lot
of mathematical analysis, and by implication probably almost all existing
physical models of the universe extant to date, we should probably leave
climbing that particular mountain for another day.
Best wishes,
Sabbir.
Uncle Al
>
> "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> news:Pine.GSO.4.30.010929...@fraser.sfu.ca...
>
> > My point is simple. The group is intended for serious discussion
> > of physics *as*that*is*construed*by*the*moderators. They get to
> > make the descisions, as it is they who have accepted the
> > thankless task of moderating. If you disagree with their
> > decisions then you are free to create your own group.
>
> Well it would be nice if they were not to have such blatant double
> standards in their application of the newsgroup charter to which
> they purport to adhere.
Mitra was demonstrably incorrect. To what standards should one
adhere? Science discards demonstrably wrong proposals. Garbage.
Dead. No apologies tendered or necessary. Let Mitra become a
priest. Religion dotes upon the empirically disproven - test of
faith!
[snip]
You don't have rights in moderated newsgroups, you have granted
privileges. Mitra violated the news group charter by being
1) Demonstrably wrong,
2) Prolix about it;
3) Boring;
4) Ineducable;
5) And a purveyor of snit.
It is one thing to make an error; it is another to insist upon it.
In real science corpses stay dead. Go into psychology, economics,
social sciences... where everything and its opposite are true and
majority vote decides reality. HAH!
--
Matthew Nobes
last word if he wishes.
On Mon, 1 Oct 2001, Sabbir Rahman wrote:
> "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> news:Pine.GSO.4.30.010929...@fraser.sfu.ca...
>
> > My point is simple. The group is intended for serious discussion
> > of physics *as*that*is*construed*by*the*moderators. They get to
> > make the descisions, as it is they who have accepted the
> > thankless task of moderating. If you disagree with their
> > decisions then you are free to create your own group.
>
> Well it would be nice if they were not to have such blatant double
> standards in their application of the newsgroup charter to which
> they purport to adhere. While they may have the right to do this
> on the basis that it is their newsgroup and that they are the
> moderators, it certainly doesn't say much for their character or
> for their scientific objectivity.
>
> > Please. The claims that Mitra is making are refuted hundreds (if
> > not thousands) of times a year by graduate students takeing GR
> > classes.
>
> Yes, graduate students can certainly be naive, unassuming and
> gullible, which is not surprising given that they believe
> they are being handed down knowledge from the world-leading
> experts in their fields. I took those classes too, and I
> think I would be a little more weary if I were to take them a
> second time.
Perhaps you had bad teachers. My teachers to date have, for the
most part, encouraged active questioning, and independent
thought.
> > ...His writings (at least those that you posted) reveal
> > deep misunderstandings of GR.
> ...
> > > [...] except for the case that
> > > the first may be mathematically decidable in a given
> > > theoretical model.
> >
> > Sure, and it has been decieded. Go read Penrose and Hawking
> > papers of the early seventies. They proved lots of theorems,
> > which are widely accepted by mathmaticians.
> >
> > If Mitra is correct where is the flaw in Penrose's proof?
>
> Your claims are statements of faith.
No they are based on the fact that I have reviewed the Hawking
and Penrose proofs and found no obvious flaws. I have not
preformed a detailed analysis, but that didn't seem needed.
> They do not constitute an objective scientific analysis of
> Mitra's work, and in that sense differ little in content from
> Hillman's "critique". Where, specifically is the error in
> Mitra's work?
I told you that, you snipped it out. He is claiming that there
is something going on at R=2m which is clearly false.
> Clearly you believe Mitra to be a crackpot purely on the
> basis of his conclusions, which happen to contradict your
> (and others') beliefs.
I think he's a crackpot because he seems incapable of recognizing
his errors. A sure sign of a crackpot.
> Mitra has clearly shown the error in Oppenheim & Snyder's
> work which originally lead to the proposal of the existence
> of black holes, and to date has not failed, on request, to
> show where others have made mistakes. To date, no-one has
> succeeded in finding an error in Mitra's analysis, which is
> presumably why his work has eventually been accepted for
> publication. And this was certainly not for want of trying by
> the many referees of his work.
Umm, sure thing. From LANL it looks like he's published one
paper (on this subject) in Foundations of Physics Letters. This
is not a GR journal. Try Classical and Quantum Gravity or Phys.
Rev. D.
> If you would kindly let me know which proofs of black hole
> formation by Penrose and Hawking you are referring to, I will
> happily pass them on to Abhas Mitra for his response.
Umm, if he's not aware of these proofs he needs to learn more GR.
They are considered among the most profound work on GR since
Einstein.
> And if you could also let me know which of Penrose's proofs
> Mitra's work is contradicting,
The one that says that for any physially reasonable energy
momentum tensor, any asymtotically flat solution to the field
equations will contain a closed trapped surface.
That's from memory, see Hawking and Eillis for an exact
statement.
> I will pass that on too. Or would I be correct in supposing
> that you have no specific proof in mind, and are merely
> appealing to Penrose and Hawking's established reputations as
> if this somehow constitutes indisputable evidence for your
> claims?
No I am appealing to mathmatical proofs about the field
equations. Just like I can confidently state that Fermat's last
theorem has been proven.
> [The other things were going off-topic, albeit interesting, so
> let's leave those discussions for another day. With the exception
> of the following...]
>
> > When you come up with a theory that reproduces more experimental
> > results then GR+SM let me know.
[snip discussion of unpulished work]
> Besides the standard model possibly isn't even renormalisable
> - see the work of Cheng on the hep-th archives. Again, a
> discussion for another day, perhaps.
Umm nothing I said relied on the renormalizablity of the SM to be
true, you're just dodging. Assume a hard cutoff of 25 TeV if you
like (note this has to do with the renormalization group,
discussion of which you snipped).
off to the killfile editor now...
James Hunter
Uncle Al wrote:
> Sabbir Rahman wrote:
> >
> > "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> > news:Pine.GSO.4.30.010929...@fraser.sfu.ca...
> >It is one thing to make an error; it is another to insist upon it.
>
>
> In real science corpses stay dead. Go into psychology, economics,
> social sciences... where everything and its opposite are true and
> majority vote decides reality. HAH!
Corpses stay dead in real *politics*.
At least "science" is finally fessing up to what it actually is:
Holistic Crapola.
Aleksandr Timofeev
>
> > Let's assume you are corect, (I don't really think so, but I'll
> > play along for a bit) the qustion is so what?
> > [snip]
>
> If Mitra is correct, it means that the scientific establishment
> has misunderstood GTR for at least the last seventy years or so.
> Severable notable personalities have built careers (and published
> many popular books) based upon these misconceptions, and have
> unwittingly been deceiving not only themselves but also the
> general public all this time. If nothing else, it would be quite
> an embarassment for the scientific establishment, particularly as
> so many naive followers believe in and defend outpourings of the
> establishment with such fervent religious fanaticism.
>
> The modern-day scientific method is simplistic, narrow-minded,
> fallible and a great hindrance to scientific advancement - as
> indeed are many of the scientists who so ardently put their
> faith in it. It is high time we recognised these problems and
> made some concerted efforts to fix it.
Direct experimental confirmation of your statements
is adduced here:
http://groups.google.com/groups?ic=1&q=msgid:3B372CA5%40MailAndNews.com
>
> Best wishes,
>
> Sabbir.
Aleksandr Timofeev
> On Sat, 29 Sep 2001, Sabbir Rahman wrote:
>
> > "Matthew Nobes" <man...@fraser.sfu.ca> wrote in message
> > news:Pine.GSO.4.30.010928...@fraser.sfu.ca...
> >
> > > Let's assume you are corect, (I don't really think so, but I'll
> > > play along for a bit) the qustion is so what?
> > > [snip]
>
> that the moderators of sci.physics.research are under no
> obligation to accept his post in any case.
>
> It is tremedously hypocritcal of you to accuse others of academic
> misconduct, while doing it yourself. Please quote me in context
> next time.
>
> > establishment has misunderstood GTR for at least the last
> > seventy years or so.
>
>
> Seriously, he seems to be claiming that there is a curvature
> singularity at R=2M. This is nonsense (the curvature invariants
> are finite there). I've done the calculation myself (as have
> thousands of grad students).
>
> Like I said, the myth of the lone researcher overturning the
> ``establishment'' is just that, a myth.
>
> > published many popular books) based upon these
> > misconceptions, and have unwittingly been deceiving not only
> > themselves but also the general public all this time. If
> > nothing else, it would be quite an embarassment for the
> > scientific establishment, particularly as so many naive
> > followers believe in and defend outpourings of the
> > establishment with such fervent religious fanaticism.
>
> don't know what you are talking about.
>
> > fallible and a great hindrance to scientific advancement
>
> experiments!
>
> statement. Modern physics has produced agreement between theory
> and experiment to absolutly astonishing levels.
Please, give explanation to this phenomenon:
http://groups.google.com/groups?ic=1&q=msgid:3B372CA5%40MailAndNews.com
1. Empirical gravitational regularities of a symmetry in the Solar System
1.1. Magic ratios of linear combinations of planetary masses
Here are the most reliable values of the Solar System [1] planetary
masses that can be experimentally obtained by celestial mechanics:
Table I
Planetary masses and Ratios of linear combinations of masses
Planet Symbol Mass | Ratio Exact Rounded
used for value | considered value ratio
each planet Earth=1 | of the ratio
. |
Jupiter MJU or 1 317.735 |(MJU+MSA)/(MUR+MNE) = 12.9959 ~ 13
Saturn MSA or 2 95.147 | MJU/(MUR+MNE) = 10.0010 ~ 10
Neptune MNE or 3 17.23 | MSA/(MUR+MNE) = 2.9948 ~ 3
Uranus MUR or 4 14.54 | (MJU+MSA)/MNE = 23.9630 ~ 24
Earth MTE or 5 1.000 | MUR/(MTE+MVE) = 8.0110 ~ 8
Venus MVE or 6 0.815 | (MNE+MUR)/MVE = 38.9816 ~ 39
Mars MMA or 7 0.108 | (MTE+MVE)/MME = 33.0000 ~ 33
Mercury MME or 8 0.055 | MVE/(MMA+MME) = 5.0000 ~ 5
The difference between computed values of ratios and the closest
integer can possibly be explained by an effect similar (Francis Aston 1920)
to mass modification caused by dense packing in atom nucleii. The planetary
masses are measured with some errors also.
1.2. Chiral symmetry ratios of linear combinations of the planetary masses
When organised graphically, the ratios [2] of linear combinations of
the planetary masses considered, reveal a chain of gravitational
correlations between triples of planets possessing chiral symmetry:
Table II
Chiral symmetry ratios of linear combinations of the planetary masses
10
I<----------->|
I 13 |
I<==============>I
I | I
? 39 I | I
|<----------------->I 33 |<---------------->I 24 | I
| |<------------------>I |<----------------->I
| | I ? | | I 5 | | I 8 | | I 3 | | I
| | I<====>| | I<====>| | I<====>| | I<====>| | I
| | I | | I | | I | | I | | I
10 9 I 8 7 I 6 5 I 4 3 I 2 1 I
I | | I | | I | | I | | I
I Mercury MarsI Venus EarthI Uran NepI Saturn JupiterI
I I I I I
10+9 8+7 6+5 4+3 2+1
ln(mass)
- - -------------------------------------------------------------->
The following symbols here are used in this graphic:
MSA + MJU <-> 2 + 1; MUR + MNE <-> 4 + 3;
MVE + MTE <-> 6 + 5; MME + MMA <-> 8 + 7;
MJU <-> 1; MSA <-> 2; MNE <-> 3; MUR <-> 4;
MTE <-> 5; MVE <-> 6; MMA <-> 7; MME <-> 8;
5
Direct gravitational correlation - <====>;
33
Reverse gravitational correlation - <---------->
Note: Here it is necessary to understand exclusive importance of
the numbers Fibonacci for gravitational regularities inside
the Solar system in common case:
If you look at direct gravitational connections than you will see the
following numbers: 3, 5, 8, 13.
For the third hypothetical quad there should be now following numbers
accordingly: 21 and 34.
[snip]
...
> How do you define ``scientific advancement''?
>
> > - as indeed are many of the scientists who so ardently put
> > their faith in it. It is high time we recognised these
> > problems and made some concerted efforts to fix it.
>
> You have a proposal that would make the scientific method
> infallible? I'm all ears.
Please, give explanation to this phenomenon.
Aleksandr Timofeev
[snip]
> Can you point out one reproducable expeirment that is being
> coveniently ignored?
http://groups.google.com/groups?ic=1&q=msgid:3B372CA5%40MailAndNews.com
> The most obvious experiment that might conflict with GR (Pioneer
> staellites) is not being ignored.
"Nice dodge."
The publication even of any reduced version of this article
in any public issuing secretly is prohibited everywhere:
http://groups.google.com/groups?ic=1&q=msgid:3B372CA5%40MailAndNews.com
Daryl McCullough
in Mitra's calculation. Let me first state some facts about
Lemaitre coordinates and Schwarzschild coordinates for a
black hole of mass M. (I'm ignoring radial dependence,
since everything is spherically symmetric in what follows).
For simplicity of the expressions, I will work with
units so that 2GM = 1 and c = 1.
1. The metric in Schwarzschild coordinates is
ds^2 = (1 - 1/R) dT^2 - (1 - 1/R)^{-1} dR^2
2. The path of a radially infalling test particle is
described by
dR -(1-1/R)
--- = ---------- [E^2 -(1-1/R)]^{1/2}
dT E
where E is a constant.
3. E = 1 for a particle falling from
rest infinitely far from the Black Hole.
4. When E = 1, we have
dR/dT = -(1-1/R) (1/R)^{1/2}
5. The metric in Lemaitre coordinates is (again,
ignoring angular part)
ds^2 = dt^2 - 1/R dr^2
where R = [3/2 (r-t)]^{2/3}
6. The differential relationship between Lemaitre coordinates
and Schwarzschild coordinates is
dr = dT + R^{1/2} (1 - 1/R)^{-1} dR
dt = dT + R^{-1/2} (1 - 1/R)^{-1} dR
7. For a particle falling from rest infinitely
far from the Black Hole, we already know that
dR = -(1-1/R) (1/R)^{1/2} dT (from 4). Plugging
this expression for dR into equation 6 gives
a. dr = dT - R^{1/2} (1 - 1/R)^{-1} (1 - 1/R) (1/R)^{1/2} dT
= dT - dT
= 0
b. dt = dT - R^{-1/2} (1 - 1/R)^{-1} (1 - 1/R) (1/R)^{1/2} dT
= (1-1/R) dT
So, for a freefalling particle, starting from rest at infinity,
in Lemaitre coordinates, dr = 0, and dt = (1-1/R) dT.
8. In Lemaitre coordinates, then, dr/dt = 0 for such a
freefalling particle.
9. For such a freefalling particle,
ds^2 = dt^2 - 1/R dr^2
= dt^2 - 0
= dt^2
So, ds = dt for such a particle.
Okay, let's go to Mitra's calculation. It's basically the same
as mine (except for factors of 2GM) until he gets to this point:
>Since t is the comoving time, we have
>
> dt = (1-2M/R)^{1/2} dT (8)
That's not correct. The full expression relating
Lemaitre time t to Schwarzschild time is
dt = dT + R^{-1/2} (1 - 1/R)^{-1} dR
For the particular case of a freefalling particle falling
from infinity, this yields the relationship (my equation 7b.)
dt = dT (1 - 1/R)^{-1}
>Now by using the above equations, it can be found that,
>
> (dr/dt)^2 = 1 at R = R_g (9)
I don't think that's true, if dr and dt are interpreted
as Lemaitre coordinates. Instead, (dr/dt) = 0 (my equation 7a.)
>Hillman also writes that "it is true that the coordinate slope equals to
>-1 here"; by 'here' he means at R=2M. To verify the correctness of
>Eq.(9), however, it would be better to see the Eq. 3.12.5, pp. 112 of
>Zeldovich and Novikov, Rel. Astrophysics, Vol. 1, Univ of Chicago (1971):
>
> (dr/dt) = +/- (R_g/R)^{1/2} (3.12.5) of ZN
I think that you've made the wrong interpretation of dr/dt here.
This equation should be (in your notation)
dR/dt = +/- (R_g/R)^{1/2}
To see this, note that, for a free-falling particle, we
have (in Schwarzschild coordinates R and T) (my equation 4.)
dR/dT = -(1-1/R) (1/R)^{1/2}
To get the rate of change of R in Lemaitre time coordinates,
we use
dR/dt = (dR/dT) (dT/dt)
From my equation 7b, we know that for a freefalling particle,
dT/dt = (1-1/R)^{-1}. So we get
dR/dt = -(1-1/R) (1/R)^{1/2} (1-1/R)^{-1}
= - (1/R)^{1/2}
or, reinserting the factors of 2MG,
dR/dt = (2MG/R)^{1/2}
>Note that the tau of ZN is our t, r of ZN is our R and vice-versa, and
>recall that we have taken c=G=1.
>
>By putting Eq.(9) in Eq.(6) one can find that INDEED
>
> ds^2 = 0 at R=R_g=2M following the radial geodesic. (10)
No, we get (my equation 9.)
ds^2 = dt^2
That's the whole point of the Lemaitre coordinates, that
for a freefalling particle, dt = ds.
--
Daryl McCullough
CoGenTex, Inc.
Ithaca, NY
Massimiliano Malgieri
> John,
> Sabbir Rahman has brought to our attention what appears to
> be a very severe case of anti-science bias in the 'moderation'
> of sci.physics.research, in that you permit an unprovoked
> and intemperate attack on a serious scientist, but you reject
> a measured and thoughtful response, one which would allow
> people to make up their own minds. I was inclined to make
> a strong comment, but I waited because I thought it was only
> fair to give you or the other moderators a chance to explain
> or apologise. You have had that chance, and you have
> thrown it away.
>
Hi Martin,
I am just a long-time lurker here (and in sci.phyisics.research also),
but I want to express to you my admiration for such an equilibrate,
careful, objective, but still forceful, in one word just perfect post.
You have exactly expressed the feelings i had about this case, better
than I ever could have done (and not only because of language
problems).
Maybe what John Baez is thinking now is that you are just an unusual
kind of crackpot using this case to march against the estabilishment.
Or maybe he is not. Anyway, I am a regular orthodox physicist, and I
exactly share your feelings. Maybe this might count something in the
mind of John Baez, or again, maybe not. Maybe the fact that I agree
with you on this matter is sufficient to make me a crackpot too. I
don't know, let's see what happens.
I'm sorry the first time you hear my voice it's basically a "me too",
but i just had to tell you.
Massimiliano Malgieri
David de Hilster
> 1) in my experiance (and that is fairly consierable) 99% of
> ``crackpot'' theories don't make testable predictions. The few
> ``alterante'' theorys that do make them, aren't crackpot at all
> (the best example is the work of Ilja Schmelzer).
>
> 2) some ``crackpot'' theories have been tested. And found false
> (see the SLAC experimetn which disproved autodynamics).
In your own words: nice dodge.
It's amazing how people just spread "stuff" without
investigating themselves.
The SLAC experiment did not disprove or prove anything.
It was flawed. A new experiment has been proposed.
http://www.autodynamics.org/new99/Experiments/index.html
Of course, you should have known this already, right?
God, how it's amazing how much misinformation is spread
in these pathetic zoos people call "newsgroups".
> Nice dodge.
Again, you chose your own words well for youself!
-David de Hilster
Charles Francis
Sabbir Rahman <intuit...@yahoo.com> writes
>Dear Friend and Colleagues,
>
>It is with some disappointment and reluctance that I am forwarding
>this message to the sci.physics and sci.physics.relativity newsgroups,
>which are unmoderated. I hope, nevertheless, that it will be given due
>consideration by those readers of this newsgroup who are open-minded
>and sincere enough to seek scientific truths even if they seem to go
>against their mathematical or physical "intuition".
>
>On 19th July, 2001, a rather scathing attack was made by Chris Hillman
>on the work of Abhas Mitra, regarding the formation and existence of
>black holes (or rather, lack thereof). This is still available on the
>sci.physics.research archives:
>
>http://www.lns.cornell.edu/spr/2001-07/msg0034336.html
>
>undignified, being full of personal attack and "flames" and is
>clearly quite contrary to the charter of the sci.physics.research
>newsgroup.
Readers will no doubt recall that I have found Chris to be somewhat OTT
on a number of occasions in the past, but having looked at this post it
appears to me that he merely says that Mitra's paper could be seen to be
absurd and incompetent by an undergraduate student of general
relativity. That does not appear to be a flame, but is a simple
statement of fact.
Regards
--
Charles Francis
Charles Francis
<mtgra...@btinternet.com> writes
>
>Sabbir Rahman has brought to our attention what appears to
>be a very severe case of anti-science bias in the 'moderation'
>of sci.physics.research, in that you permit an unprovoked
>and intemperate attack on a serious scientist, but you reject
>a measured and thoughtful response, one which would allow
>people to make up their own minds.
And yet, in response to a quote about this "scientist's" work
>>Surely there must be some mathematical errors in this work?
you say
>No doubt. There are certainly many in all his previous works.
and then
>The problem seems to be that Mitra's papers fall into the category of
>"not even wrong". When I last looked at one of his papers there was
>no matter of finding the point where an error was made and the
>calculation deviated from correctness, it was just off from the
>get-go.
and yet
>This is an appalling application of double standards, and
>I hope that you realise how appalling it is, but I suspect
>that you don't, or that you couldn't care less. If you do
>care, the good news is that it still isn't too late for you
>to indicate that my suspicions are unfounded.
But by your previous para the moderators are just doing their job.
Regards
--
Charles Francis
Charles Francis
>detailed rejoinder to it, including mathematical details, which I
>forwarded to the newsgroup. This rejoinder was rejected by the
>moderator, Matt McIrvin, on the basis that it contained "personal
>(i) Mitra's rejoinder was a completely justified and direct response
>to Hillman's abusive posting
Hillman's post was a blunt but fair assessment of Mitra's claims.
>, and (ii) was much tamer in content
>besides, with logical mathematical arguments being presented to show
>the mathematical misconceptions in Hillman's original posting.
Hillman's post did not seem to contain misconceptions about general
relativity or cosmology. It may have contained misconceptions about the
model Mitra is using, but if Mitra is saying, as seems to be suggested,
that his results are true of general relativity then this is tantamount
to a claim that every mathematician bar Mitra who has ever studied the
subject is completely incompetent. That is what I call a flame, and it
is you who is guilty of it, not Hillman.
It seems highly improbable that Mitra is capable of putting together
logical mathematical arguments, but if he is he should admit that he is
working on a completely speculative model with very little relation to
what is currently understood of cosmology.
You should not expect such overspeculative model to be accepted by
s.p.r. since it was formed precisely so that readers would not need to
wade through garbage in order to assess its worth.
>
>Both Abhas Mitra and myself independently complained to Matt McIrvin,
>expressing our surprise at his rejection of the rejoinder. To this
>we have yet to have, nor do we any longer expect, a response. Matt
>McIrvin did suggest that if we sent a version without the personal
>attacks, he would consider it for posting. On this basis I prepared a
>second version (appended below). This has neither appeared on the
>sci.physics.research newsgroup, nor has McIrvin had the courtesy to
>give an explanation as to why.
At this point you should have e-mailed the moderators at physics-
research...@ncar.ucar.edu, enclosing a copy of the missing post.
Posts do go astray, and they do moderate posts which have been rewritten
addressing the original reason for rejection. If they still have reason
for rejection, they will tell you. But do not expect them to analyse the
mathematics for mistakes. In any case that has been done by a number of
posters here.
Regards
--
Charles Francis
Sabbir Rahman
news:9p2ig...@drn.newsguy.com...
> So, the proper time ds is related to Schwarzschild coordinate time dt by
>
> ds = (1 - 2GM/r) dt
>
> This is such an incredibly simple result, I feel like there's probably
> some way to get to it immediately from the Schwarschild metric, but I
> don't see how right now.
>
> Anyway, this (I think) is what caused Abhas Mitra to say that
> at the event horizon, ds = 0. Because at the event horizon
> r = 2GM, the term multiplying dt goes to zero.
>
> However, this doesn't imply that ds = 0, it seems to me. The problem
> is that, because the Schwarzschild coordinates are singular at r = 2GM,
> t goes to infinity in a finite amount of proper time. So the expression
>
> ds = (1 - 2GM/r) dt
>
> is an indefinite form at GM/r. The first term (1 - 2GM/r)
> goes to zero as the geodesic crosses the event horizon, but
> the second term dt goes to infinity. You can't evaluate the
> product without further analysis.
>
> That further analysis has been done, by switching to different
> coordinates, such as Kruskal-Szekeres coordinates, which are
> not singular at r = 2GM. The proper time ds then turns out to
> be nonzero for crossing from just above the event horizon to
> just below the event horizon.
[I am forwarding the following response on behalf of Abhas Mitra - apologies
for the delay - I think he is working on answering all of the mathematical
objections which were raised one by one, and which I have just sent him. If the
language used sounds a bit weird, it is probably my fault.]
And so, to Mitra's response...]
*************
It seems that McCullough has correctly found that for a test particle
falling towards a BH by starting from R=infinity, we have
ds/dT = (1- 2M/R) (1)
so that at the EH, R=2M, we have
ds/dT = 0 (2)
We know that if there is a fraction y/x=0, it is possible that
x=infinity; but it is a matter of elementary calculus that if
dy/dx = 0, we can only have dy=0 and NOT dx= infinity. If y is the
distance and x is the time, dx cannot be 1000s or 1s or 0.000001s or indeed
assume any finite value, let alone being infinity. By definition dx is an
infinitesimal, otherwise we cannot apply calculus at all and Eqs. such as
(1) would be meaningless.
Thus there is no reason not to conclude that Eq. 2 implies
ds=0 at EH, R=2M. (3)
However it may be worthwhile to recall that while dT is always infinitesimal,
Delta T or Delta x can be infinite. If the test particle falls from
R=R_1 to R=2M, it is known that
Delta T = T(R=2M) - T(R_1) = infinity (4)
It seems likely that McCullough may have confused Delta T in (4) (which
is indeed infinite) with dT (R=2M) which is an infinetisimal. To crosscheck
this point, on referring to Mitra's paper:
Found. Phys. Lett. 13(6), 543 (2000)
we find that Eq. 3 can be derived by avoiding any confusion between dT
and Delta T:
As mentioned in Mitra's paper,
(dR/dT)^2 = (1-2M/R)^2 [E^2- (1-2M/R)]/E^2 (5)
As R -> 2M, or (1-2M/R) -> 0,
(dR/dT)^2 -> (1-2M/R)^2 (6)
or,
dT^2 (1-2M/R) -> dR^2/(1-2M/R) (7)
so that the radial part of the Sch. metric
ds^2 = dT^2 (1-2M/R) - dR^2/(1-2M/R) -> 0 as R-> 2M (8)
which is essentially Eq. 2 and here one does not need to confront
the question of whether dT is an infinetisimal (which it is) or infinity
(which it is not).
McCullough has written that if one uses Kruskal coordinates it can be
found that ds>0 rather that ds=0 at R=2M. Browsing through many GTR books
one fails to see any such calculation. On the other hand, one finds in
Mitra's posting that, if u and v are the Kruskal coordinates,
du^2 = dv^2 at R=2M
so that the radial part of Kruskal metric
ds^2 = (16 M^2/e) (du^2- dv^2) =0 at R=2M (9)
in conformity with Eq. 2.
--
Posted from berkleysquare-2.dsl1.easynet.co.uk [217.204.233.98]
Sabbir Rahman
news:9p7tu2$j2b$1...@woodrow.ucdavis.edu...
Dear Steve,
I forwarded your message to Abhas Mitra, and I am sending the following
comments on his behalf...
Best wishes,
Sabbir
***********************************
I think Carlip has correctly reaffirmed the dictum that "Once timelike,
always timelike". However the entire mathematical analysis of Carlip can
be carried out over [any] region which does not contain a true physical
singularity - even though it may contain a coordinate singularity.
A close reading of Mitra's paper/posting reveals that he has used Carlip's
result to arrive at the conclusion that the EH is not a mere coordinate
singularity, but rather, a true physical singularity. [According to Mitra's
analysis], as a test particle approaches the EH along a radial worldline,
ds^2 ->0 as R ->2M. But by Carlip's result, had the EH been a truly
non-singular region, we must have had ds^2 ->0 even as R-> 2M. This
violation, in Mitra's opinion, indicates that the EH is not a non-singular
region but a truly singular region of spacetime. As Mitra argues, for a
BH, the true singularity lies only at R=0, and therefore the two
situations, R=2M and R=0 must be representing the [same] region. In other
words, he concludes, M=0 for the supposed BH.
Sabbir Rahman
> Seriously, he seems to be claiming that there is a curvature
> singularity at R=2M. This is nonsense (the curvature invariants
> are finite there). I've done the calculation myself (as have
> thousands of grad students).
I am forwarding some comments on this statement from Abhas Mitra
on his behalf...
Sabbir.
********************************
Response to the Comment that there is no curvature singularity at EH
The curvature scalar [satisfies],
K ~ M^2/R^6
and at the EH, R=2M,
K~ 1/R^4 ~ 1/M^4
Thus K can indeed blow up at the EH if the gravitational mass of the
BH is M=0. So what needs to be verified is whether the derivations leading
to the conclusion M=0 are correct or not.
To delve a little deeper into this matter, one can take a look at Mitra's
preprint:
On the question of Trapped surfaces and BHs (astro-ph/0105532)
There he has mentioned that by using the acceleration 4-vector, one can
construct an Acceleration SCALAR (not just the radial component of
4-acceleration):
M
a = ----------------
R^2 Sqrt (1-2M/R)
Mitra argues that if the EH were a mere coordinate singularity, no relevant
scalar would blow up there. But clearly, even if one starts with the
assumption that M >0, this SCALAR 'a' blows up at R=2M. In Mitra's opinion,
this is a confirmation that the EH is the true singularity of the BH. But
the true singularity, as we know, lies at R=0. Therefore, he argues that
R=2M and R=0 describe the same physical situation implying M=0.
Sabbir Rahman
news:kJ8aGsAE...@clef.demon.co.uk...
> And yet, in response to a quote about this "scientist's" work
>
> >>Surely there must be some mathematical errors in this work?
>
> you say
>
> >No doubt. There are certainly many in all his previous works.
>
Dear Charles,
You seem to have gotten yourself into a bit of a muddle! :)
I suggest you take another closer look at who exactly said what
and reformulate your attack as appropriate.
Best wishes,
Sabbir.
tj Frazir
to change and cowards of debait . They base physics on popular
speculation . Its the ignorant just because it dose club . Fuck em
Joe Fischer
: In article <2463c4a5587b36feb41...@mygate.mailgate.org>,
: Sabbir Rahman <intuit...@yahoo.com> writes
:>I made Abhas Mitra aware of Hillman's posting, and he prepared a
:>detailed rejoinder to it, including mathematical details, which I
:>forwarded to the newsgroup. This rejoinder was rejected by the
:>moderator, Matt McIrvin, on the basis that it contained "personal
:>attacks" against Chris Hillman. This of course was surprising, as
:>(i) Mitra's rejoinder was a completely justified and direct response
:>to Hillman's abusive posting
:
: Hillman's post was a blunt but fair assessment of Mitra's claims.
I am confused here, was an article by Mitra
ever published in s.p.research?
If not, why was Hillman writing there about it,
is Hillman a moderator there now, or was Hillman allowed
to read a Mitra submission and respond there without
Mitra's paper being accepted?
Is there something fishy going on?
Joe Fischer
--
3
Matthew Nobes
> In sci.physics.relativity Charles Francis <cha...@clef.demon.co.uk> wrote:
> : In article <2463c4a5587b36feb41...@mygate.mailgate.org>,
> : Sabbir Rahman <intuit...@yahoo.com> writes
> :>I made Abhas Mitra aware of Hillman's posting, and he prepared a
> :>detailed rejoinder to it, including mathematical details, which I
> :>forwarded to the newsgroup. This rejoinder was rejected by the
> :>moderator, Matt McIrvin, on the basis that it contained "personal
> :>attacks" against Chris Hillman. This of course was surprising, as
> :>(i) Mitra's rejoinder was a completely justified and direct response
> :>to Hillman's abusive posting
> :
> : Hillman's post was a blunt but fair assessment of Mitra's claims.
>
> I am confused here, was an article by Mitra ever published in
> s.p.research?
To the best of my knowledge, no.
> If not, why was Hillman writing there about it,
> is Hillman a moderator there now, or was Hillman allowed
> to read a Mitra submission and respond there without
> Mitra's paper being accepted?
> Is there something fishy going on?
No. IIRC rswomebody (not Mitra) posted a link to Mitra's
preprint on LANL and said something to the effect of ``what do
people think of this?''. Dr. Hillman responed with a critque.
That's it, nothing fishy.
Further, the moderators of s.p.research are all capable of
recognizing Mitra's error, they wouldn't need outside help.
Joe Fischer
:> In sci.physics.relativity Charles Francis <cha...@clef.demon.co.uk> wrote:
:> : In article <2463c4a5587b36feb41...@mygate.mailgate.org>,
:> : Sabbir Rahman <intuit...@yahoo.com> writes
:> :>I made Abhas Mitra aware of Hillman's posting, and he prepared a
:> :>detailed rejoinder to it, including mathematical details, which I
:> :>forwarded to the newsgroup. This rejoinder was rejected by the
:> :>moderator, Matt McIrvin, on the basis that it contained "personal
:> :>attacks" against Chris Hillman. This of course was surprising, as
:> :>(i) Mitra's rejoinder was a completely justified and direct response
:> :>to Hillman's abusive posting
:> :
:> : Hillman's post was a blunt but fair assessment of Mitra's claims.
:>
:> I am confused here, was an article by Mitra ever published in
:> s.p.research?
:
: To the best of my knowledge, no.
Then his work should not be topical there.
:> If not, why was Hillman writing there about it,
:> is Hillman a moderator there now, or was Hillman allowed
:> to read a Mitra submission and respond there without
:> Mitra's paper being accepted?
:> Is there something fishy going on?
:
: No. IIRC rswomebody (not Mitra) posted a link to Mitra's
: preprint on LANL and said something to the effect of ``what do
: people think of this?''. Dr. Hillman responed with a critque.
Dr. Hillman could have ignored the link, and
spent the time writing an original article rather
than bashing.
If the link had no merit nobody wants to
read about it, people do like good original papers.
: That's it, nothing fishy.
I think under those circumstances a response
by Mitra should be accepted even if remarks critical
of the group have to be removed by the moderator.
: Further, the moderators of s.p.research are all capable of
: recognizing Mitra's error, they wouldn't need outside help.
Then Hillman's article should have been
rejected, what purpose is there in bashing?
Oh, I get it, it is an ego builder for mathematicians
who dabble in physics.
Joe Fischer
--
3
Gerry Quinn
>Seriously, he seems to be claiming that there is a curvature
>singularity at R=2M. This is nonsense (the curvature invariants
>are finite there). I've done the calculation myself (as have
>thousands of grad students).
The calculation involves a change of coordinates, and it is IMO by no
means possible to assume without question that the change is legitimate
as a matter of *physics* as distinct from a matter of *general
relativity*. Indeed, if gravity is modelled as a field, it isn't - and
such a model nevertheless works fine in the asymptotically flat
spacetime outside a black hole. That must surely give rise to questions
in any open mind.
Thus, while the event horizon doesn't seem to have to be a singularity,
it can be. Given that treating it as a singularity eliminates the
thermodynamically questionable interior solutions, I don't really have
much interest in whether, as Mitra suggests but most deny, general
relativity has contradictions in the black hole interior.
The GR interior, with its mathematically malignant central singularity,
paper-doll topologies, and similar hideous artifacts, is unnecessary and
surely unattractive compared to a 'frozen star' with a benign
singularity at the event horizon where normal low-energy physical
processes stop.
- Gerry Quinn
Charles Francis
<da...@cogentex.com> writes
>So, the proper time ds is related to Schwarzschild coordinate time dt by
>
> ds = (1 - 2GM/r) dt
>
>This is such an incredibly simple result, I feel like there's probably
>some way to get to it immediately from the Schwarschild metric, but I
>don't see how right now.
Its part of a general relationship to do with red shift, coming from the
relationship
g_ab = h_ij x^i_,a x^j_,b
where h_ij is identical to the Minkowski metric
which gives you a red shift factor (or rather the reciprocal)
x^0_,0 = (1-2GM/r)^(1/2)
relating time at the centre of co-ordinates to time for a static object
at radius r.
Then to find proper time for an inertial object, you observe that
g_ab = h_i'j' x^i_,a x^j_,b
where h_i'j' is now the Minkowski metric for the frame of the inertial
object, so you now have x^0'_,0 = (1-2GM/r)^(1/2)
which gives you two multiplies by the same factor, getting rid of the
square root.
(sorry I couldn't face doing any more of the notation in ASCII, so I'll
just leave you with this outline. I have a paper which treats red shift
factors as more fundamental, and certainly simpler to work with, than
the metric), it should be on lanl tomorrow, with the provisional number
http://arXiv.org/abs/physics/0110007
Regards
--
Charles Francis
Daryl McCullough
>And so, to Mitra's response...]
>McCullough has written that if one uses Kruskal coordinates it can be
>found that ds>0 rather that ds=0 at R=2M. Browsing through many GTR books
>one fails to see any such calculation. On the other hand, one finds in
>Mitra's posting that, if u and v are the Kruskal coordinates,
>
> du^2 = dv^2 at R=2M
No, that's not correct.
In units where 2GM = c = 1, the Kruskal coordinates
can be written in terms of the Schwarzschild coordinates
as
u = 2 exp(f/2) cosh(t/2)
v = 2 exp(f/2) sinh(t/2)
where f = r + log(r-1).
The differential form is this
du = df exp(f/2) cosh(t/2) + dt exp(f/2) sinh(t/2)
dv = df exp(f/2) sinh(t/2) + dt exp(f/2) cosh(t/2)
So
du^2 - dv^2 = exp(f)(df^2 - dt^2)
where I used cosh^2(t/2) - sinh^2(t/2) = 1.
Now, let's write everything in terms of the
Schwarzschild radius, r.
f = r + log(r-1)
df = df/dr dr = (1 + 1/(r-1)) dr
= (1 - 1/r)^{-1} dr
exp(f) = exp(r)(r-1)
dt = dr/(dr/dt)
= - r^{1/2}(1 - 1/r)^{-1} dr
where I used dr/dt = - r^{-1/2} (1-1/r) for a freefalling
particle (falling from rest at infinity).
So, in terms of r
du^2 - dv^2 = exp(r)(r-1) ((1 - 1/r)^{-2} - r (1-1/r)^{-1}) dr^2
= exp(r)(r-1) (1-1/r)^{-2}(1-r) dr^2
= - exp(r) (r-1)^2 (1-1/r)^{-2} dr^2
= - exp(r) r^2 dr^2
The expression for ds^2 in Kruskal coordinates is
ds^2 = - exp(-r) r^{-1} (du^2 - dv^2)
= r dr^2
This is not zero at the event horizon r=1.
The same result could have been obtained from
the Schwarzschild coordinates. As I derived
in a previous post, for a freefalling particle
(falling from rest at infinity)
ds = (1-1/r) dt
Substituting for dt in terms of dr, we get
ds = - (1-1/r) r^{1/2}(1 - 1/r)^{-1} dr
= - r^{1/2} dr
At r=1, this is again not zero.
Robert Karl Stonjek
ASCII, so I'll
just leave you with this outline. I have a paper which treats red shift
factors as more fundamental, and certainly simpler to work with, than
the metric), it should be on lanl tomorrow, with the provisional number
http://arXiv.org/abs/physics/0110007
RKS: I like to make myself useful by finding useful links and interesting
papers and posting the URLs to other groups around the place. The URL you
gave leads to a dialogue box asking for a username and password. If I can't
get at it, others will probably also have problems. Your browser probably
remembers your details and passes them quietly in the background each time
you log on to that site. So you may not have been aware.
If you intended your URL to apply only to members or password holders then
please ignore this message, otherwise you might consider placing your paper
in some public domain.
Kind Regards,
Robert Karl Stonjek.
PS doing several things simultaneously sometimes bares fruit (like trying to
get the paper while writing this note). To get around the password problem
interested parties can first go to http://arxiv.org/abs/physics
then type in 0110007 in the dialogue box and hit <Return> or <Enter>.
this will take you to the abstract where you can then click on the 'Paper:
PDF only' link that will down load the PDF file.
Charles inadvertently gave us the owner's link that allows additions,
deletions and updates of papers (I think).
Hope this has been of some help!! :)
Martin Gradwell
> In article <2463c4a5587b36feb41...@mygate.mailgate.org>,
> Sabbir Rahman <intuit...@yahoo.com> writes
> >I made Abhas Mitra aware of Hillman's posting, and he prepared a
> >detailed rejoinder to it, including mathematical details, which I
> >forwarded to the newsgroup. This rejoinder was rejected by the
> >moderator, Matt McIrvin, on the basis that it contained "personal
> >attacks" against Chris Hillman. This of course was surprising, as
> >(i) Mitra's rejoinder was a completely justified and direct response
> >to Hillman's abusive posting
>
> Hillman's post was a blunt but fair assessment of Mitra's claims.
If you will permit me to be equally blunt, just for a moment:
"-Of course- you are flat out wrong, completely incorrect
and very quicky debunked! Your absurd (and very incorrect)
conclusion illustrates your confusion and inability to
understand the simplest points. Of course it is absurd!
It is a ludicrous claim which anyone can see right away
is dead wrong. It is quite frankly so riddled with -elementary-
misstatements and misconceptions as to be not only worthless
but frankly embarrassing. You are terribly confused. Anyone
so thoroughly confused in his own mind cannot possibly express
himself clearly. It is very regrettable that your post was
(shame! shame!) actually -published."
Blunt indeed.
I could never compose original statements in
that style, but I didn't have to. I just strung
together a few phrases from Dr. Hillman's "blunt
but fair" post.
Am I being unfair?
Well then, you can reply, saying exactly how I am being
unfair. But Dr. Mitra cannot reply to the unprovoked
assault on him in sci.physics.research. Is that fair?
>
> >, and (ii) was much tamer in content
> >besides, with logical mathematical arguments being presented to show
> >the mathematical misconceptions in Hillman's original posting.
>
> Hillman's post did not seem to contain misconceptions about general
> relativity or cosmology. It may have contained misconceptions about the
> model Mitra is using, but if Mitra is saying, as seems to be suggested,
> that his results are true of general relativity then this is tantamount
> to a claim that every mathematician bar Mitra who has ever studied the
> subject is completely incompetent.
I presume, then, that you do not classify Albert Einstein
as a mathematician.
In 1939, Dr. Einstein wrote a paper which concluded "The
essential result of this investigation is a clear understanding
as to why the Schwarzschild singularities do not exist in
physical reality".
This was not a brief and obviously erroneous flirtation with
heterodoxy. When Einstein died twenty-six years later, he was
still just as sure about the absence of singularities as he
was in 1939. He changed his mind on many points, most famously
on the cosmological constant, but he never believed in black
holes. He was the quintessential source of GR - you could say
that while he lived he was GR - and none of the other experts
who had access to him were able to convince him that he was in
error on this point. If he was still around today, the
establishment would be forced to deride him as a crank.
Fortunately he is safely dead, so they can choose instead to
ignore practically everything that he said, and pretend that
black holes are a great vindication of his ideas, and that
an attack on black holes is an attack on his memory.
> That is what I call a flame, and it
> is you who is guilty of it, not Hillman.
There is nothing that could begin to describe the
logical horror perpetrated in the sentence above.
Words fail me. Even the string of Hillmanisms
near the top of this post doesn't come close.
>
> It seems highly improbable that Mitra is capable of putting together
> logical mathematical arguments, but if he is he should admit that he is
> working on a completely speculative model with very little relation to
> what is currently understood of cosmology.
Whereas if he were to write approvingly about
wormholes and about the complete gravitational
collapse of gravitational waves, that wouldn't
be speculative at all, because that is what
modern cosmology is all about?
>
> You should not expect such overspeculative model to be accepted by
> s.p.r. since it was formed precisely so that readers would not need to
> wade through garbage in order to assess its worth.
You should not assess the worth of an argument by
studying only travesties of it. Any forum which
allows only one side of an argument to be advanced
is worthless to anybody with an open mind.
But perhaps sci.physics.research was not created
for such people.
Whatever the reasons for its formation, s.p.research
seems to exist now mainly in order to protect the closed
-minded against any intrusions of reality. That is why
Rahman's posts are rejected, but Uncle Al has no such
trouble.
Martin Gradwell, mtgra...@btinternet.com
http://www.btinternet.com/~mtgradwell/
--
Posted from host213-1-129-49.btinternet.com [213.1.129.49]
Martin Gradwell
news:d36ccd46.01100...@posting.google.com...
> Hi Martin,
> I am just a long-time lurker here (and in sci.phyisics.research also),
> but I want to express to you my admiration for such an equilibrate,
> careful, objective, but still forceful, in one word just perfect post.
> You have exactly expressed the feelings i had about this case, better
> than I ever could have done (and not only because of language
> problems).
Thank you for your kind words, Massimiliano.
I appreciate them very much. I hope that I will
be able to live up to them. I think that you
have expressed yourself well, so that there is
no need for you to worry about language problems.
If other posters refer to such problems, it will
only be because they have no valid arguments.
> Maybe what John Baez is thinking now is that you are just an unusual
> kind of crackpot using this case to march against the estabilishment.
> Or maybe he is not. Anyway, I am a regular orthodox physicist, and I
> exactly share your feelings. Maybe this might count something in the
> mind of John Baez, or again, maybe not. Maybe the fact that I agree
> with you on this matter is sufficient to make me a crackpot too. I
> don't know, let's see what happens.
I have had no significant interaction with John Baez,
so I have reached no firm conclusion, but my strong
suspicion is that his crackpot index is intended to
include all who are not of his opinion. You are not
of his opinion, so...
My ideas tend to be unorthodox, but I understand how
it is possible to be both orthodox and open-minded.
If orthodox ideas just happen to make more sense to
you than any alternatives that you know of, but you
are open to new alternatives, then you are more than
just a regular orthodox physicist. Your approach ought
to be common but it isn't, at least not in usenet.
>
> I'm sorry the first time you hear my voice it's basically a "me too",
> but i just had to tell you.
>
> Massimiliano Malgieri
Thanks again. It can be a good idea to dip
your toe in the water before taking a swim.
I hope that you will find posting here to be
an enjoyable and rewarding experience, and
that you will continue to do so.
Robert Karl Stonjek
Academic Science" and he seems to be saying pretty much what you are saying.
He discovered high redshift QSO (quasars) near low redshift galaxies
(particularly the Seyfert class of galaxy) as early as the 1960s, but has
all sorts of trouble getting his results published.
And he is no minnow of the cosmology world. Other scientists make claims
about his results that would equally call into question there own (such as
connecting filaments being part of the noise flaw of the test instrument or
resulting data). However, when data agrees with current theory, it is
readily accepted but when it is contrary, it must be so much better, perhaps
more accurate than anyone else's data.
If someone of Arp's standing is muted (and his data muted, including data
gathered by many third parties around the world) then what hope has dissent
got? This is not how physics was done in the first half of the 20th
century - most of the famous scientists in the area of quantum physics and
cosmology offered theories and data that was contrary to the point of
destruction of the then current theories - even overthrowing Newton (at
least that is how it may well have been viewed).
Had Einstein been born 100 years later, his theories would not have faired
anywhere nearly as well.
George Jones
> Sabbir says...
>
> >And so, to Mitra's response...]
>
> >McCullough has written that if one uses Kruskal coordinates it can be
> >found that ds>0 rather that ds=0 at R=2M. Browsing through many GTR books
> >one fails to see any such calculation. On the other hand, one finds in
> >Mitra's posting that, if u and v are the Kruskal coordinates,
> >
> > du^2 = dv^2 at R=2M
ds > 0 and ds = 0 are both possible at R = 2M ! However, only one is
correct for an observer that crosses the event horizon.
You have considered the case of an radially infalling observer. Anywhere
along the oberserver's timelike worldline, including where the worldline
intersects the event horizon R = 2M, ds^2 > 0 and ds > 0. You have
calculated this below.
Mitra, on the other hand, considers (though he will disagree) a
spacetime curve that is timelike above the event horizon, and that after
reaching the event horizon, never leaves the event horizon. As Steve
Carlip has demonstrated, this is impossible for a geodesic.
From what you have below,
u^2 - v^2 = 4 exp(f).
At R = 2 M, f = -oo, so u = +/- v. Hence, for any curve that stays along
the event horizon, du = +/- dv, du^2 = dv^2, ds^2 = 0. This just says
that the event horizon is a lightlike hypersurface.
So, as you said in another post, Mitra considers a curve that changes
from timelike to lightlike.
I've just restated what you've done in a slightly way in the unlikely
event that it sheds some light on the situation.
Regards,
George
Matthew Nobes
> In article
> <Pine.GSO.4.30.01092...@fraser.sfu.ca>,
> Matthew Nobes <man...@fraser.sfu.ca> wrote:
>
> >Seriously, he seems to be claiming that there is a curvature
> >singularity at R=2M. This is nonsense (the curvature
> >invariants are finite there). I've done the calculation
> >myself (as have thousands of grad students).
>
> The calculation involves a change of coordinates, and it is
> IMO by no means possible to assume without question that the
> change is legitimate as a matter of *physics* as distinct
> from a matter of *general relativity*.
I've no idea what you are getting at here Gerry. Mitra is
claiming something about GR, and it's wrong, period. If you want
to argue that GR is not the correct theory, fine, but *WITHIN*GR*
black holes exist.
> Indeed, if gravity is modelled as a field, it isn't - and
> such a model nevertheless works fine in the asymptotically
> flat spacetime outside a black hole. That must surely give
> rise to questions in any open mind.
Huh? You lost me totally here.
> Thus, while the event horizon doesn't seem to have to be a
> singularity, it can be.
No it can't be if you stay within the mathmatical formalism of
GR.
> Given that treating it as a singularity eliminates the
> thermodynamically questionable interior solutions, I don't
> really have much interest in whether, as Mitra suggests but
> most deny, general relativity has contradictions in the black
> hole interior.
>
> The GR interior, with its mathematically malignant central
> singularity, paper-doll topologies, and similar hideous
> artifacts, is unnecessary and surely unattractive compared to
> a 'frozen star' with a benign singularity at the event
> horizon where normal low-energy physical processes stop.
Huh? What the hell is *any* of that supposed to mean? First off
a singularity is a singularity, whether it's at R=2M R=0 or R=10
cubits. Second, GR is a *CLASSICAL* field theory. ALL SUCH
THEORIES have singularities of exactly the same form. Maxwell's
E&M has an *IDENTICAL* singularity to the Swarzchild metric (1/R
divergence).
I honestly cannot imagine what your point is, but whatever it is
it has nothing to do witht he fact that in GR there is a
singularity at R=0 for a point mass solution. Just like E&M.
Charles Francis
<sto...@ozemail.com.au> writes
>Charles Francis: (sorry I couldn't face doing any more of the notation in
>ASCII, so I'll
>just leave you with this outline. I have a paper which treats red shift
>factors as more fundamental, and certainly simpler to work with, than
>the metric), it should be on lanl tomorrow, with the provisional number
>http://arXiv.org/abs/physics/0110007
>
>RKS: I like to make myself useful by finding useful links and interesting
>papers and posting the URLs to other groups around the place.
I will much appreciate any peer review process you can give, as I wish
to advertise this paper to explain relativity, special & general, on the
NG.
>The URL you
>gave leads to a dialogue box asking for a username and password. If I can't
>get at it, others will probably also have problems. Your browser probably
>remembers your details and passes them quietly in the background each time
>you log on to that site. So you may not have been aware.
Its the right URL, but lanl password protect it until the new listing
goes out (that's why I said tomorrow). That has now happened and the
password is no longer needed.
http://arXiv.org/abs/physics/0110007
An Intuitive Approach to Special and General Relativity
Author: Charles Francis
Comments: A reformulation with the pedagogical purpose of introducing
simplified concepts and techniques for a mathematical treatment, 23
pages, 20 figures
The k-calculus was advanced by Hermann Bondi as a means of explaining
special relativity using only simple algebra (Bondi H.: Relativity and
Common Sense, London, Heinemann, 1964). As used by Bondi, k is Doppler
shift. This paper extends the k-calculus to include gravitational red
shift and to develop techniques for an introductory treatment of general
relativity in which the emphasis is on mathematical deduction from
physical measurement procedure. Using ideas of geometric optics,
geodesic motion is understood from the refraction of the wave function
due curvature. The k-calculus gives a very simple derivation of
Schwarzschild, showing that the geometry is equivalent to the existence
of a fundamental minimum time, proportional to rest mass, between the
interactions of elementary particles. The Newtonian approximation is
seen from direct application of red shift to the wave function. Finally
differential geometry is introduced, showing that the k-calculus gives
an equivalent treatment of general relativity up to and including the
general form of Einstein's field equation.
Regards
--
Charles Francis
Charles Francis
Matthew Nobes <man...@fraser.sfu.ca> writes
> If you want
>to argue that GR is not the correct theory, fine, but *WITHIN*GR*
>black holes exist.
I know this is off the point you were making, Matthew, but I'm not sure
whether we really ought to say that, at least if what one means by it is
the singularity. What we ought to say its that quantum gravity effects
are likely to become important near the event horizon (as we already
know from Hawking radiation) and that classical general relativity is
likely to break down so that we don't know what happens inside.
Hawking radiation is obviously idealised, assuming no other particles
for the pair to interact with. But really there should be a huge density
of other particles accumulating outside the event horizon. Hawking
radiation may just be a mechanism which causes these particles to
radiate away, without ever crossing the event horizon.
I think I'd even put money on it. But for now I'll just bet ten virtual
dollars that when we have a theory of quantum gravity we find that
nothing actually gets as far as the event horizon before being radiated
away.
Regards
--
Charles Francis
Gerry Quinn
>On Tue, 2 Oct 2001, Gerry Quinn wrote:
>
>> In article
>> <Pine.GSO.4.30.01092...@fraser.sfu.ca>,
>> Matthew Nobes <man...@fraser.sfu.ca> wrote:
>>
>> >Seriously, he seems to be claiming that there is a curvature
>> >singularity at R=2M. This is nonsense (the curvature
>> >invariants are finite there). I've done the calculation
>> >myself (as have thousands of grad students).
>>
>> The calculation involves a change of coordinates, and it is
>> IMO by no means possible to assume without question that the
>> change is legitimate as a matter of *physics* as distinct
>> from a matter of *general relativity*.
>
>I've no idea what you are getting at here Gerry. Mitra is
>claiming something about GR, and it's wrong, period. If you want
>to argue that GR is not the correct theory, fine, but *WITHIN*GR*
>black holes exist.
I agree he's claiming something about GR, and I agree that most
everybody seems convinced that he's wrong (albeit there's little
evidence that they are being convinced by reductio ad absurdums or
anything of that sort).
My point really was that I don't think interior black hole GR solutions
refer to anything physical, which in turn makes these arguments angel
and pin-related. Just two years ago, I'd have had a lot of people here
jumping down my throat for saying that. Does anybody really believe in
the interior solutions any more, I wonder?
>> Indeed, if gravity is modelled as a field, it isn't - and
>> such a model nevertheless works fine in the asymptotically
>> flat spacetime outside a black hole. That must surely give
>> rise to questions in any open mind.
>
>Huh? You lost me totally here.
Questions about exactly where GR breaks down.
>> Thus, while the event horizon doesn't seem to have to be a
>> singularity, it can be.
>
>No it can't be if you stay within the mathmatical formalism of
>GR.
Perhaps one can have one foot in and one out, by saying that some
descriptions within a particular mathematical formalism are 'closer' to
descriptions in an more general theory than others?
>> Given that treating it as a singularity eliminates the
>> thermodynamically questionable interior solutions, I don't
>> really have much interest in whether, as Mitra suggests but
>> most deny, general relativity has contradictions in the black
>> hole interior.
>>
>> The GR interior, with its mathematically malignant central
>> singularity, paper-doll topologies, and similar hideous
>> artifacts, is unnecessary and surely unattractive compared to
>> a 'frozen star' with a benign singularity at the event
>> horizon where normal low-energy physical processes stop.
>
>Huh? What the hell is *any* of that supposed to mean? First off
>a singularity is a singularity, whether it's at R=2M R=0 or R=10
>cubits. Second, GR is a *CLASSICAL* field theory. ALL SUCH
>THEORIES have singularities of exactly the same form. Maxwell's
>E&M has an *IDENTICAL* singularity to the Swarzchild metric (1/R
>divergence).
I think there's an important point you are missing. If we talk about a
theory that's not quite GR but has much in common with it, on which a
singularity exists at the event horizon, such a singularity is a benign
one insofar as we know what it means (future times in certain coordinate
systems are never reached, and must be replaced by times in which
certain normally very slow quantum processes have occurred, outside
the scope of GR). Colloquially, ordinary events freeze. We can easily
think about such singularities - GR breaks down, but in a way we can
easily understand.
The central singularity, by contrast, is a monster. Nobody knows what
it means or how GR would break down there. In truth, it doesn't really
make sense at all, and the reason is that a few too many coordinate
changes have brought us too far from the realms of the physical.
The situation with regard to Maxwell's theory is entirely different.
For a start the theory applies in flat spacetime. That makes the
singularity easy to interpret. We can get right in close to it and
presumably at some energy scale we see new structure. But in the case
of the supposed central singularity of a black hole, we have to think
very hard even about what it would mean to get close to it.
>I honestly cannot imagine what your point is, but whatever it is
>it has nothing to do witht he fact that in GR there is a
>singularity at R=0 for a point mass solution. Just like E&M.
What it has to do with it is to point out how irrelevant it is. It's as
relevant as whether there are contradictions in SR in the tachyon
regime.
- Gerry Quinn
Charles Francis
Martin Gradwell <mtgra...@btinternet.com> writes
>"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
>news:1nh+dfAy...@clef.demon.co.uk...
>>
>
>If you will permit me to be equally blunt, just for a moment:
>
>"-Of course- you are flat out wrong, completely incorrect
>and very quicky debunked! Your absurd (and very incorrect)
>conclusion illustrates your confusion and inability to
>understand the simplest points. Of course it is absurd!
>It is a ludicrous claim which anyone can see right away
>is dead wrong. It is quite frankly so riddled with -elementary-
>misstatements and misconceptions as to be not only worthless
>but frankly embarrassing. You are terribly confused. Anyone
>so thoroughly confused in his own mind cannot possibly express
>himself clearly. It is very regrettable that your post was
>(shame! shame!) actually -published."
>
>Blunt indeed.
>I could never compose original statements in
>that style, but I didn't have to.
I can, and worse, though generally I prefer not to. Hillman has actually
been the brunt of some of my most acute attacks.
The fact is that Mitra does appear to be flat out wrong, completely
incorrect and very quickly debunked, and confused abut the simplest
points.
But to put back in some of the text Hillman actually wrote:
Mitra claims that the tangent vectors to a timelike geodesic in the
Schwarzschild vacuum must become -null- at the event horizon r = 2m;
this is of course completely incorrect!
we can now see that what Hillman wrote when he used this phrase was a
simple statement of fact, unless of course that is not Mitra's claim at
all. But you have not protested that Hillman misrepresented Mitra's
claim, only that he said that the claim, as reported, was completely
incorrect, which it is.
> I just strung
>together a few phrases from Dr. Hillman's "blunt
>but fair" post.
>
>Am I being unfair?
Yes. Because you put together a lot of remarks which were made about
specific and separate claims of Dr Mitra.
Again putting Hillman's words back in:
(3) Mitra claims that the Kruskal-Szekeres chart has a coordinate
singularity at r = 2m; this absurd (and very incorrect) conclusion may
also be very quickly debunked
You have not said that this is not Mitra's claim. But it is, as Hillman
says, a completely ludicrous claim, and anyone putting a paper on lanl
making it would have to be so incompetent that they should be ashamed to
live.
> But Dr. Mitra cannot reply to the unprovoked
>assault on him in sci.physics.research. Is that fair?
I can tell you the moderators on s.p.r. hate me because I am constantly
challenging assumptions at the foundations of science, and posing
unorthodox views, I have teased John Baez on numerous occasions. But I
still get through most of the time. I am convinced Dr Mitra can reply,
if he can do so in rational terms based on an understanding of physics.
But do not expect human beings always to have perceptions of what is
fair which coincide with yours, and if Mitra hopes to defend the claims
which Hillman says he makes, then I would not expect him to be able to
post there.
Of course if Hillman has misrepresent Mitra, that would be different.
But all you appear to be saying is that incompetence should not be
called incompetence, and I can't go along with you there.
There is a very great deal of difference between believing that a theory
of quantum gravity will completely change our understanding of event
horizons and black holes, which I do, and simply getting general
relativity wrong, which is what Mitra seems to do.
>> It seems highly improbable that Mitra is capable of putting together
>> logical mathematical arguments, but if he is he should admit that he is
>> working on a completely speculative model with very little relation to
>> what is currently understood of cosmology.
>
>Whereas if he were to write approvingly about
>wormholes and about the complete gravitational
>collapse of gravitational waves, that wouldn't
>be speculative at all, because that is what
>modern cosmology is all about?
Much work is done on solutions to equations which may not hold under
circumstances which we do not yet understand, but doing such solutions
may be one way to gain insight into the problem.
>
>> You should not expect such overspeculative model to be accepted by
>> s.p.r. since it was formed precisely so that readers would not need to
>> wade through garbage in order to assess its worth.
>
>You should not assess the worth of an argument by
>studying only travesties of it. Any forum which
>allows only one side of an argument to be advanced
>is worthless to anybody with an open mind.
>But perhaps sci.physics.research was not created
>for such people.
I am only judging on the ground of what Hillman says Mitra is saying. If
Mitra is really saying something completely different, the case against
Hillman is that he has not understood Mitra, and should not comment. But
so far you have only complained about what Hillman has to say about the
views of Mitra as reported. And for those points I understand, Hillmans
comments are accurate with regard to the reported views of Mitra.
Regards
--
Charles Francis
Steve Carlip
>What we ought to say its that quantum gravity effects
> are likely to become important near the event horizon (as we already
> know from Hawking radiation) and that classical general relativity is
> likely to break down so that we don't know what happens inside.
While it's possible that this is true (and some string theorists argue
that it is), it's not at all certain, and I would hesitate to even say that
it's ``likely''. It's almost certainly true that quantum gravitational
effects become important near the place that the classical singularity
would be, and it's very likely that they become important near Cauchy
horizons (places where causality breaks down classically). But the
gravitational field at the event horizon of a black hole can be very
small---by increasing the mass, you can make the curvature tensor
as small as you like---and it's not clear that local quantum effects
should be important.
Note that an accelerating observer, with arbitrarily small acceleration,
sees a Rindler horizon that's locally indistinguishable from a black
hole horizon. But I don't think you would say that classical general
relativity must break down in that case, and that quantum gravitational
effects must drastically change the behavior of the world as soon as
you begin accelerating.
There *is* an argument that quantum gravity becomes important at
the horizon, but it requires that the theory be extremely nonlocal,
and that special relativity break down for large boosts. This could
turn out to be right, but it's definitely not obviously right.
Steve Carlip
Matthew Nobes
> In article <Pine.GSO.4.30.011002...@fraser.sfu.ca>, Matthew Nobes <man...@fraser.sfu.ca> wrote:
> >On Tue, 2 Oct 2001, Gerry Quinn wrote:
> >
> >> In article
> >> <Pine.GSO.4.30.01092...@fraser.sfu.ca>,
> >> Matthew Nobes <man...@fraser.sfu.ca> wrote:
> >>
> >> >Seriously, he seems to be claiming that there is a curvature
> >> >singularity at R=2M. This is nonsense (the curvature
> >> >invariants are finite there). I've done the calculation
> >> >myself (as have thousands of grad students).
> >>
> >> The calculation involves a change of coordinates, and it is
> >> IMO by no means possible to assume without question that the
> >> change is legitimate as a matter of *physics* as distinct
> >> from a matter of *general relativity*.
> >
> >I've no idea what you are getting at here Gerry. Mitra is
> >claiming something about GR, and it's wrong, period. If you
> >want to argue that GR is not the correct theory, fine, but
> >*WITHIN*GR* black holes exist.
>
> I agree he's claiming something about GR, and I agree that
> most everybody seems convinced that he's wrong (albeit
> there's little evidence that they are being convinced by
> reductio ad absurdums or anything of that sort).
Huh? There's been quite a few convincing arguements as to why
he's wrong. I give one above.
> My point really was that I don't think interior black hole GR
> solutions refer to anything physical,
Fine, so you are essentially saying that GR doesn't apply within
the EH.
> which in turn makes these arguments angel and pin-related.
> Just two years ago, I'd have had a lot of people here jumping
> down my throat for saying that. Does anybody really believe
> in the interior solutions any more, I wonder?
I think you are confusing exotica with astrophysically relvent
solutions. For example, the Oppenhiemer-Snyder model, apart from
the central singularity, is physical throughout. A ball of dust
collapses, under it's own graviational interaction, until it is
contracted to a single point. Now the final bit of that is
unphysical, but much of what happend behind the EH isn't.
For example consider a spherically symmetric dust ball of one
solar mass. The EH in this case is IIRC around 3km. Are you
claiming that once all the matter passes through that radius what
is going on is no longer determined by the OS model?
> >> Indeed, if gravity is modelled as a field, it isn't - and
> >> such a model nevertheless works fine in the asymptotically
> >> flat spacetime outside a black hole. That must surely give
> >> rise to questions in any open mind.
> >
> >Huh? You lost me totally here.
>
> Questions about exactly where GR breaks down.
But why would it break down at the EH? Again, forget about
exotic solutions and focus on something astrophysically relvant.
> >> Thus, while the event horizon doesn't seem to have to be a
> >> singularity, it can be.
> >
> >No it can't be if you stay within the mathmatical formalism of
> >GR.
>
> Perhaps one can have one foot in and one out, by saying that
> some descriptions within a particular mathematical formalism
> are 'closer' to descriptions in an more general theory than
> others?
Sure, if you have said ``more general theory'' I'm all ears.
Huh? GR doesn't ``break down'' in any way at an EH.
A relvent example from a related field. There has been much work
of late on ``acoustic black holes''. I gather that one can set
up a region in a fast flowing fluid (supersonic IIRC) that will
trap sound waves in an analgous way to the trapping of light at
an EH. But nobody would claim that the laws of hydrodynamics are
breaking down at this ``acoustic'' event horizon.
> The central singularity, by contrast, is a monster.
No it isn't.
> Nobody knows what it means
Sure we do. It's a consquence of using classical field theory in
a region where you're not supposed to.
> or how GR would break down there.
Granted, we don't have a quantum theory of gravity yet.
> In truth, it doesn't really make sense at all, and the reason
> is that a few too many coordinate changes have brought us too
> far from the realms of the physical.
This arguement does not follow from anything else you have said.
The singularity at r=0 is coordinate independent. Use a frame of
reference in which you are 100000 parsecs away orbiting a neutron
star at 3/10 times the speed of light. It doesn't matter.
> The situation with regard to Maxwell's theory is entirely
> different.
Really? Becuase where I'm from 1/R is the same as 1/R.
> For a start the theory applies in flat spacetime. That makes
> the singularity easy to interpret.
Really? How? Until QED people had a devil of a time
interpreting the singularity in Maxwell's theory. Indeed many
``big brains'' (like Dirac and Lorentz) have given it much
thought.
It's only easy to interpret in *RETROSPECT*.
> We can get right in close to it and presumably at some energy
> scale we see new structure. But in the case of the supposed
> central singularity of a black hole, we have to think very
> hard even about what it would mean to get close to it.
No we don't. In a metric theory the notion of distance between
two points is well defined. The central singularity is one
point, your position is another. To get ``closer'' to the
singularity simpley minimize the distance between these two
points. Not much thinking needed.
> >I honestly cannot imagine what your point is, but whatever it is
> >it has nothing to do witht he fact that in GR there is a
> >singularity at R=0 for a point mass solution. Just like E&M.
>
> What it has to do with it is to point out how irrelevant it
> is. It's as relevant as whether there are contradictions in
> SR in the tachyon regime.
??? I have no idea what you are trying to get at.
Charles Francis
<car...@dirac.ucdavis.edu> writes
>In sci.physics Charles Francis <cha...@clef.demon.co.uk> wrote:
>
>>What we ought to say its that quantum gravity effects
>> are likely to become important near the event horizon (as we already
>> know from Hawking radiation) and that classical general relativity is
>> likely to break down so that we don't know what happens inside.
>
>While it's possible that this is true (and some string theorists argue
>that it is), it's not at all certain, and I would hesitate to even say that
>it's ``likely''. It's almost certainly true that quantum gravitational
>effects become important near the place that the classical singularity
>would be, and it's very likely that they become important near Cauchy
>horizons (places where causality breaks down classically). But the
>gravitational field at the event horizon of a black hole can be very
>small---by increasing the mass, you can make the curvature tensor
>as small as you like---and it's not clear that local quantum effects
>should be important.
What I am actually thinking about is the matter falling in through the
event horizon. It seems to me that this would become very dense and very
hot, a least from the point of view of an outside observer, and that it
would considerably alter the analysis of the gravitational field, in
ways that I would hesitate to anticipate could be treated through
classical general relativity.
I am also thinking that interactions in this matter would considerably
alter Hawking radiation. Instead of the negative energy particle falling
in through the event horizon it may interact or annihilate with a
positive energy particle also falling towards the event horizon. On a
purely intuitive basis I might think that the amplitude for this process
would be considerably greater than for unmodified Hawking radiation, and
perhaps that a massive black hole with a lot of matter falling in would
radiate at a much higher rate than Hawking's prediction. If I could
think of a way to do a calculation I might even hope to find a mechanism
for quasars. But I can't. Nonetheless I generally hope that if I ponder
like this for long enough, then eventually I may see how to do a
calculation.
>Note that an accelerating observer, with arbitrarily small acceleration,
>sees a Rindler horizon that's locally indistinguishable from a black
>hole horizon. But I don't think you would say that classical general
>relativity must break down in that case, and that quantum gravitational
>effects must drastically change the behavior of the world as soon as
>you begin accelerating.
Absolutely not. It is the high energy soup of infalling matter which I
think will change the situation. I have no problem with the idea of a
Rindler horizon (although I do have a problem with the amount of power
needed to sustain an acceleration long enough to actually see one!)
>There *is* an argument that quantum gravity becomes important at
>the horizon, but it requires that the theory be extremely nonlocal,
>and that special relativity break down for large boosts.
My belief is that the locality condition of quantum field theory will
survive, perhaps in some rewritten form. But I have been working from a
notion that there is some quantum sense in which one can say that an
electron (or other Dirac particle such as quark) in an eigenstate of
position is a naked singularity with a "size" equal to its Schwarzschild
radius, and that a black hole is a conglomeration of such naked
singularities. If this is the case, then I don't think it will be
possible to use the structure of a manifold inside the Schwarzschild
radius of the conglomeration, any more than it is possible to say that
an electron in a wave state has the property of position in ordinary
quantum mechanics.
Regards
--
Charles Francis
Charles Francis
Matthew Nobes <man...@fraser.sfu.ca> writes
> For example, the Oppenhiemer-Snyder model, apart from
>the central singularity, is physical throughout. A ball of dust
>collapses, under it's own graviational interaction, until it is
>contracted to a single point. Now the final bit of that is
>unphysical, but much of what happend behind the EH isn't.
It ceases to be physical at the point when the dust becomes hot enough
that an analysis which does not treat it from a quantum point of view
breaks down. I think the event horizon of the hole is probably
significant, just as I think the Schwarzschild radius of each elementary
particle is significant for the unification qft and gtr, by featuring in
the description of the gravity of an elementary particle.
>> In truth, it doesn't really make sense at all, and the reason
>> is that a few too many coordinate changes have brought us too
>> far from the realms of the physical.
>
>This arguement does not follow from anything else you have said.
>The singularity at r=0 is coordinate independent. Use a frame of
>reference in which you are 100000 parsecs away orbiting a neutron
>star at 3/10 times the speed of light. It doesn't matter.
Mathematically it doesn't matter, but Gerry's point is valid. If the
mathematical model is not a perfect model of physics then repeating an
operation too many times can take you so far away from the physics that
the maths becomes meaningless. And none of us were really saying gr is
perfect in the first place, we're all waiting on quantum gravity.
>No we don't. In a metric theory the notion of distance between
>two points is well defined. The central singularity is one
>point, your position is another. To get ``closer'' to the
>singularity simpley minimize the distance between these two
>points. Not much thinking needed.
It is a question of when we can correctly apply a metric theory of
distance. We can do it in familiar circumstances, but for matter falling
in through the event horizon it is not so obvious that we can. The fact
of counter intuitive results is enough to dissuade Gerry from wanting
to. But for physicists who live with too many counter intuitive results
an know they are correct, it seems reasonable to suspend disbelief and
study the maths any way.
My own reason for thinking the event horizon is significant has more to
do with my belief that the Scharzschild radius of an electron is of
fundamental significance in nature, but does coincide with the point at
which Gerry finds gr too counter intuitive to believe.
Regards
--
Charles Francis
Michael Varney
> In article <daa8abfa1d7d37d02ae...@mygate.mailgate.org>,
> Martin Gradwell <mtgra...@btinternet.com> writes
> >"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
> >news:1nh+dfAy...@clef.demon.co.uk...
> >>
> Of course if Hillman has misrepresent Mitra, that would be different.
> But all you appear to be saying is that incompetence should not be
> called incompetence, and I can't go along with you there.
In this PC age one should never say another persons work is wrong or
incorrect, but rather point out that it is "not optimally correct."
We have to take care lest more proposed policies like the intellectual
harassment amendment to sexual harassment are put forth.
http://www2.auckland.ac.nz/mdr/unipolicy.html#academic
More crap
http://borntoexplore.org/unschool/Learningaboutlearning.htm
Joe Fischer
: In this PC age one should never say another persons work is wrong or
: incorrect, but rather point out that it is "not optimally correct."
Right, somebody proposes that a star that burns
all lighter elements to iron has to cool instantly and
collapse "because it's gravity _pulls_ it into a smaller
and smaller volumw", and everybody is supposed to say,
"Oh yeah!".
Joe Fischer
--
3
ueb
> Martin Gradwell <mtgra...@btinternet.com> writes
>>"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
..
> There is a very great deal of difference between believing that a theory
> of quantum gravity will completely change our understanding of event
> horizons and black holes, which I do, and simply getting general
> relativity wrong, which is what Mitra seems to do.
^^^^^^^^^^^^^^^^^^^^^^
Exactly what Hillman insinuates that Mitra does it.
>>> It seems highly improbable that Mitra is capable of putting together
>>> logical mathematical arguments, but if he is he should admit that he is
>>> working on a completely speculative model with very little relation to
>>> what is currently understood of cosmology.
>>
>>Whereas if he were to write approvingly about
>>wormholes and about the complete gravitational
>>collapse of gravitational waves, that wouldn't
>>be speculative at all, because that is what
>>modern cosmology is all about?
> Much work is done on solutions to equations which may not hold under
> circumstances which we do not yet understand, but doing such solutions
> may be one way to gain insight into the problem.
Why do you and your collegae persistently refuse to take notice of
solutions of the same equations (as used in astrophysics) achieved
from computations ? These results get a lot more insights, and do not
lead to the problems discussed here.
>>
>>> You should not expect such overspeculative model to be accepted by
>>> s.p.r. since it was formed precisely so that readers would not need to
>>> wade through garbage in order to assess its worth.
>>
>>You should not assess the worth of an argument by
>>studying only travesties of it. Any forum which
>>allows only one side of an argument to be advanced
>>is worthless to anybody with an open mind.
>>But perhaps sci.physics.research was not created
>>for such people.
> I am only judging on the ground of what Hillman says Mitra is saying. If
> Mitra is really saying something completely different, the case against
> Hillman is that he has not understood Mitra, and should not comment. But
> so far you have only complained about what Hillman has to say about the
> views of Mitra as reported. And for those points I understand, Hillmans
> comments are accurate with regard to the reported views of Mitra.
Hillman lies about Mitra is saying, and Mitra would contradict in it,
as you can read in the initial article of this thread. That it is
kept from setting right, is a monstrous procedure, but nowadays usual.
Ulrich Bruchholz
www.markt-2000.de/patent
Martin Gradwell
> In article <daa8abfa1d7d37d02ae...@mygate.mailgate.org>,
> Martin Gradwell <mtgra...@btinternet.com> writes
..
> > I just strung
> >together a few phrases from Dr. Hillman's "blunt
> >but fair" post.
> >
> >Am I being unfair?
>
> Yes. Because you put together a lot of remarks which were made about
> specific and separate claims of Dr Mitra.
I have not claimed that my collection of remarks
was an accurate paraphrase of what Dr. Hillman wrote,
only that it was equally blunt. I think that to such
a blunt attack there ought to be a right of reply,
and I see that you have availed yourself of that
right. Good for you. Isn't it lucky for you that
you were able to reply, and in the same forum where
my remarks occurred too, so that people are likely
to see both my remarks and your reply?
>
> Again putting Hillman's words back in:
>
> (3) Mitra claims that the Kruskal-Szekeres chart has a coordinate
> singularity at r = 2m; this absurd (and very incorrect) conclusion may
> also be very quickly debunked
>
> You have not said that this is not Mitra's claim. But it is, as Hillman
> says, a completely ludicrous claim, and anyone putting a paper on lanl
> making it would have to be so incompetent that they should be ashamed to
> live.
I don't have to speak for Dr. Mitra, because he has
spoken for himself, clearly and emphatically, in the
post which began this thread. As he says:
"Now the fact is that, I HAVE NEVER EVER MADE SUCH A CLAIM
IN ANY OF MY PREPRINTS."
Dr. Mitra has dealt with Hillman's points either by
emphatic denial where Hillman has got it wrong, or by
detailed maths with numbered equations so that anyone
can point out the specific errors if they are so
inclined, instead of handwaving and generalisations.
My point is that these rebuttals are excluded from
s.p.research, so that a completely one-sided picture
is presented. Anyone restricted to that forum might
be forgiven for thinking that Dr. Mitra has no response
to any of the points raised against him, and is
exactly as he has been painted.
>
> > But Dr. Mitra cannot reply to the unprovoked
> >assault on him in sci.physics.research. Is that fair?
>
> I can tell you the moderators on s.p.r. hate me because I am constantly
> challenging assumptions at the foundations of science, and posing
> unorthodox views, I have teased John Baez on numerous occasions. But I
> still get through most of the time. I am convinced Dr Mitra can reply,
> if he can do so in rational terms based on an understanding of physics.
You can see what Dr. Mitra's response was, because it is
embedded in the post which began this thread. There is no
need to speculate about whether he can use rational terms
based on an understanding of physics. If you think he is
irrational or lacking in understanding, you can say so and
point to the specific place where you think he is in error.
You can even say it in s.p.research, and I think that you
need not fear being contradicted there.
> But do not expect human beings always to have perceptions of what is
> fair which coincide with yours, and if Mitra hopes to defend the claims
> which Hillman says he makes, then I would not expect him to be able to
> post there.
You are speculating about what Mitra might say, as if
he has not spoken. He has spoken. He has given equations,
and those equations have been mostly ignored here, and
will surely not appear in s.p. research. Your assessment
of Dr. Mitra's hopes of defending his claims tallies with
my assessment.
> Of course if Hillman has misrepresent Mitra, that would be different.
> But all you appear to be saying is that incompetence should not be
> called incompetence, and I can't go along with you there.
Mitra said
"It seems that he has not read my papers properly
and has attributed or implied several aspects which
are not contained in my papers. "
.. and in various other ways he makes it clear
that he considers himself to be misrepresented
by Hillman.
Please point out where I have said or appeared to say
that "incompetence should not be called incompetence".
...
>
> I am only judging on the ground of what Hillman says Mitra is saying.
Would it not be more logical to judge Mitra by what
Mitra is saying, given that this has been presented
to you?
> If
> Mitra is really saying something completely different, the case against
> Hillman is that he has not understood Mitra, and should not comment. But
> so far you have only complained about what Hillman has to say about the
> views of Mitra as reported.
I am not complaining here about what Hillman has to say.
I have remarked about the bluntness of his turn of phrase,
but that is all. I am not trying to make any case against
him, as he is not my target on this occasion.
..
Martin Gradwell, mtgra...@btinternet.com
http://www.btinternet.com/~mtgradwell/
--
Posted from host213-122-199-250.btinternet.com [213.122.199.250]
Robert Karl Stonjek
I posted your details at http://groups.yahoo.com/group/specialrelativity so
you may or may not get a response. There are a few scientists at that site.
BTW have you ever checked out Bo Thide's Online text book? I understand he
welcomes informed opinion and changes the text to accommodate any
corrections that peers like to make/add. It is an interesting resource.
From the web page:-
Classical Electrodynamics On-Line Textbook "Electromagnetic Field Theory"
"Welcome! You have just found the World-Wide Web site for the advanced
electrodynamics Internet textbook project."
http://www.plasma.uu.se/CED/Book/
Martin Gradwell
news:zYtu7.14247$bL3.3...@ozemail.com.au...
> Martin, I'm reading Harlton Arp "Seeing Red: Redshifts, Cosmology and
> Academic Science" and he seems to be saying pretty much what you are saying.
I'm intending to get the book. I haven't read it yet
but I've read a lot about it, and I'm looking forward to
reading it. I've read some of Halton Arp's papers.
There are similarities with what I say but also,
I believe, many differences of detail. For instance,
I would say that many apparently distant objects are
actually quite local, but the light from those objects
really has travelled as far as the redshift would
suggest. The redshift is path-length related, which
is not quite the same as being distance-related, but
not totally dissimilar either.
I use some of Dr. Arp's figures on my website, and I find
it gratifying that figures which can't possibly have been
intended to support my approach nevertheless can be
interpreted as doing so.
> He discovered high redshift QSO (quasars) near low redshift galaxies
> (particularly the Seyfert class of galaxy) as early as the 1960s, but has
> all sorts of trouble getting his results published.
I think this is partly because the established theories
cannot explain such observations, and partly because his
observations have been inextricably linked to his alternative
approach, in which redshift is not distance-related.
This would invalidate all of established cosmology, no
exceptions. A theory which so comprehensively overturns
everything that has gone before needs to explain not just
the observations which prompted it but also a whole lot
more before people will begin to consider it.
My ideas, on the other hand, just invalidate most of
modern cosmology. There's probably some aspects of it
that they leave intact, though I can't think of any
off the top of my head. :-)
> And he is no minnow of the cosmology world. Other scientists make claims
> about his results that would equally call into question there own (such as
> connecting filaments being part of the noise flaw of the test instrument or
> resulting data). However, when data agrees with current theory, it is
> readily accepted but when it is contrary, it must be so much better, perhaps
> more accurate than anyone else's data.
Yes. I think there is a lot of selective ignoring of
'inexplicable' data, so that any established theory
becomes self-fulfilling, because only observations
which confirm it will be treated as reliable.
My own approach would be to say that connecting
filaments are not noise from flawed test instruments,
but neither are they necessarily an indication that
the apparently connected galaxies really are physically
connected (and they might be more than just connected -
they might well be the same galaxy, seen twice)
If light from a distant galaxy is bent in
transit, different parts of the image can be bent to
different extents, resulting in a smeared, stretched
image looking like a filament.
> If someone of Arp's standing is muted (and his data muted, including data
> gathered by many third parties around the world) then what hope has dissent
> got? This is not how physics was done in the first half of the 20th
> century - most of the famous scientists in the area of quantum physics and
> cosmology offered theories and data that was contrary to the point of
> destruction of the then current theories - even overthrowing Newton (at
> least that is how it may well have been viewed).
I'm not convinced that there has ever been a time
when there was no selection of data to fit theories.
In every age there are heroes and villains, and
the factors which cause a theory to prevail or
data to become known aren't necessarily what we
might recognise as science.
That said, it is much harder for a new theory
to gain acceptance on its merits now, because
now it isn't just individuals that champion the
existing theories, but whole armies of scientists
and administrators and committees and conferences.
These are all on the side of inertia because they
have inherited and are the custodians of a huge
infrastructure of ideas which they have been
assured work perfectly well together. These ideas
are the culmination of a vast collaborative effort.
To suggest that they might be wrong in any way is
to profoundly insult the people behind them. It
follows that any innovator is necessarily a flamer,
and deserves to be flamed in return. :-(
>
> Had Einstein been born 100 years later, his theories would not have faired
> anywhere nearly as well.
I agree.
>
> Kind Regards,
> Robert Karl Stonjek.
Likewise,
Martin Gradwell, mtgra...@btinternet.com
http://www.btinternet.com/~mtgradwell/
--
Posted from host213-122-199-245.btinternet.com [213.122.199.245]
George Hammond
I agree there is lowbrow academic censorship on
sci.physics.research. There is on EVERY moderated
internet medium.
Same is true to a lesser degree for academic journals.
Any really original scientific discovery nowadays has to
be reported in a book.
Charles Francis
<gham...@mediaone.net> writes
That does not seem possible either. No reputable publisher will invest
in a book about new discoveries if the content has not first been peer
reviewed and published by a reputable journal.
Regards
--
Charles Francis
Charles Francis
>2. In Sec 3 of his posting, Hillman writes that "Mitra claims that the
>Kruskal-Szekers chart has a coordinate singularity at R = 2M; this absurd
>(and very incorrect) conclusion..."
>
>Now the fact is that, I HAVE NEVER EVER MADE SUCH A CLAIM IN ANY OF MY
>PREPRINTS. On the other hand, I have pointed out, in several of my
>preprints, that even if one uses the Kruskal coordinates u and v, one
>would find that the EH is a true physical singularity. In other words, I
>have derived Eq.(10) using [these] coordinates. In fact, I have done so
>in a most straightforward manner using Schwarzschild coordinates too. For
>the benefit of the serious readers, I shall, again, give below the
>essence of my proof that (du/dv)^2 =1 at R=2M in this regard:
This modified claim as it stands is still absurd. I actually think the
metric does break down at the event horizon, but that is certainly not
because of anything you can do with the formulae of general relativity.
The behaviour of the manifold at the event horizon in classical general
relativity is extremely well understood, and described in almost any
text book on the subject. To say anything different you would have to
invoke some new physical principle and formulate a theory of quantum
gravity, which Mitra does not seem to be doing.
One is forced to the conclusion that he has simply mistaken the
interpretation of the formulae, or that he is using the phrase "true
physical singularity" in some strange new way that I have not heard
before. I suspect that if he were to be able to make clear what he is
saying in language that we could all agree on, we would find that he has
nothing more to say about the event horizon than is already in the text
books.
Or is he actually invoking some part of particle physics to interpret
part of general relativity, and really talking about a quantum theory of
gravity? Given his background, maybe he subconsciously is. If so, then
he needs to get very clear about what it is and what he is doing.
Regards
--
Charles Francis
Charles Francis
Martin Gradwell <mtgra...@btinternet.com> writes
>"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
>news:XdDWzTA6...@clef.demon.co.uk...
>
>> In article <daa8abfa1d7d37d02ae...@mygate.mailgate.org>,
>> Martin Gradwell <mtgra...@btinternet.com> writes
>..
>> > I just strung
>> >together a few phrases from Dr. Hillman's "blunt
>> >but fair" post.
>> >
>> >Am I being unfair?
>>
>> Yes. Because you put together a lot of remarks which were made about
>> specific and separate claims of Dr Mitra.
>
>I have not claimed that my collection of remarks
>was an accurate paraphrase of what Dr. Hillman wrote,
>only that it was equally blunt. I think that to such
>a blunt attack there ought to be a right of reply,
So do I. But my experience of the moderators is that they don't
deliberately deny such a right. Mitra should persist in asking where his
reply has gone
>> Again putting Hillman's words back in:
>>
>> (3) Mitra claims that the Kruskal-Szekeres chart has a coordinate
>> singularity at r = 2m; this absurd (and very incorrect) conclusion may
>> also be very quickly debunked
>>
>> You have not said that this is not Mitra's claim. But it is, as Hillman
>> says, a completely ludicrous claim, and anyone putting a paper on lanl
>> making it would have to be so incompetent that they should be ashamed to
>> live.
>
>I don't have to speak for Dr. Mitra, because he has
>spoken for himself, clearly and emphatically, in the
>post which began this thread. As he says:
>
>"Now the fact is that, I HAVE NEVER EVER MADE SUCH A CLAIM
>IN ANY OF MY PREPRINTS."
Sorry, I had lost Mitra's reply in that rather long post. I read the
link to Chris's reply, and when I saw the same text at the bottom I
didn't realise Mitra's reply was sandwiched in between.
>
>Dr. Mitra has dealt with Hillman's points either by
>emphatic denial where Hillman has got it wrong, or by
>detailed maths with numbered equations so that anyone
>can point out the specific errors if they are so
>inclined, instead of handwaving and generalisations.
>
>> > But Dr. Mitra cannot reply to the unprovoked
>> >assault on him in sci.physics.research. Is that fair?
>>
>> I can tell you the moderators on s.p.r. hate me because I am constantly
>> challenging assumptions at the foundations of science, and posing
>> unorthodox views, I have teased John Baez on numerous occasions. But I
>> still get through most of the time. I am convinced Dr Mitra can reply,
>> if he can do so in rational terms based on an understanding of physics.
>
>You can see what Dr. Mitra's response was, because it is
>embedded in the post which began this thread. There is no
>need to speculate about whether he can use rational terms
>based on an understanding of physics. If you think he is
>irrational or lacking in understanding, you can say so and
>point to the specific place where you think he is in error.
No, I think the reply sandwiched in the first post of this thread should
have been posted on s.p.r. I note that it was edited from the version
originally sent to the moderators, which means we may not have been
given a fair account of the moderators reason for not posting. But I am
prepared to write to the moderators who normally respect the right of
reply, provided that the reply is reasonable physics, asking that the
reply be posted.
But I do still see an error in Mitra's reply, which I will comment on in
a direct response to it.
Regards
--
Charles Francis
grelbr
[much snippage]
> I am only judging on the ground of what Hillman says Mitra is saying.
That would sort of be the complaint in a nutshell. Open scientific
discourse does not work this way.
But then, that's not the point of s.p.r., is it?
grelbr
Gregory L. Hansen
That leaves web pages. But nobody reads those. We'll just have to face
it, there's been no new scientific discoveries reported since academic
journals became popular in the mid 19th century.
--
"'No user-serviceable parts inside.' I'll be the judge of that!"
Tom Roberts
> [quantum gravity effects at an event horizon]
> What I am actually thinking about is the matter falling in through the
> event horizon. It seems to me that this would become very dense and very
> hot, a least from the point of view of an outside observer, and that it
> would considerably alter the analysis of the gravitational field, in
> ways that I would hesitate to anticipate could be treated through
> classical general relativity.
Just think about dropping a single atom into a million-solar-mass black
hole. At the event horizon the tidal forces on that atom are less than
at the surface of the earth. Now think about dropping a billion tons of
atoms, and it becomes clear that interactions among all those atoms
can be important -- tidal forces will certainly heat them up. But
whatever happens, it is still be completely negligible compared to a
million solar masses!
> I am also thinking that interactions in this matter would considerably
> alter Hawking radiation.
For the one atom, clearly not very much. For a billion tons, possibly.
But the Hawking radiation from that million-solar-mass black hole is
only a few Watts (IIRC), and that is spread out over an enormous surface.
It may well be that at the subatomic scale the locus of the horizon
is not definitely fixed. Do you really think it is precisely defined
to an accuracy of better than 10^-18 meter over a "radius" of 10^9 meter?
If the locus of the horizon is itself subject to quantum fluctionations,
think about what that does to simplistic descriptions of "pair production
and one falls in with negative energy"....
> perhaps that a massive black hole with a lot of matter falling in would
> radiate at a much higher rate than Hawking's prediction.
Even an accretion of just a few kilograms per second would VASTLY exceed
the Hawking radiation of that million-solar-mass black hole. The
brightness of quasars is not due to Hawking radiation....
Tom Roberts tjro...@lucent.com