Shocker: Nothing Moves in Spacetime!!!
SavainL
deterministic reality. Be prepared also to believe that absolutely
nothing can move in spacetime. If this comes as a shock to you, read on.
While exchanging ideas with other posters here on sci.physics, I was
astonished to discover that many students of relativity assumed that
spacetime was this extremely rigid yet curvable geometric structure. We
are indeed taught that matter curves spacetime which in turn affects the
motion of matter. It does seem to make sense. Kinda. Most people have
no understanding of general relativity. Even physicists will admit to not
having a proper understanding of it and those who claim to understand it
cannot explain it to those who don't. Strange...
It turns out that there's a little known aspect of spacetime (the
backbone of general relativity) that is almost never taught to students of
physics. It is so disturbing and revealing that general relativists are
seldom willing to discuss it. I first heard about it a little over a year
ago from a physics professor with whom I had corresponded in the past. He
sort of mentioned it nonchalantly, and I made nothing of it at the time.
I simply put it in a back corner of my mind for later retrieval. Recently
I had the opportunity to bring it out to the forefront of my consciousness
and the "fit hit the shan", so to speak. Here it is:
NOTHING MOVES IN SPACETIME!!!
The spacetime concept was created because physicists believed that time
could be viewed as one of the 4 dimensions of reality. The problem with
making time a dimension is that it renders spacetime completely
motionless. I mean dead, changeless, unchangeable. Spacetime is a 100%
deterministic structure in which nothing can change from the infinite past
to the infinite future!!! Why? Because, if you try to change anything in
spacetime you end up with a circularity. Change requires time. But time
is already part of the structure!!! It's like saying time changes over
time. See the problem? It is completely intractable. Yet countless
physicists are willing to live with it as if the problem weren't there.
Albert Einstein taught us that the motion of matter is governed by the
geometry of spacetime. We are told that spacetime is extremely rigid: it
is mostly flat except in the vicinity of massive bodies. Matter has the
ability to curve spacetime around it, a phenomenon which results,
according to general relativists, in what we commonly experience as
gravity. But how can matter curve spacetime if spacetime cannot change?
Well, you might say, maybe spacetime is already pre-curved in the
infinite future. This introduces a new dilemma which flies in the face of
the logic of cause and effect. One of the things we know about cause and
effect is that a cause must precede its effect. So if spacetime is
precurved, how can this curvature be caused by massive bodies? I
understand that this may be a little hard to think about (I had a hard
time seeing the problem at first) but almost anyone should be able to
figure out. It's not really all that hard.
This is one of the most damaging pieces of information I know of that
one can use against the idea of spacetime. Spacetime requires a 100%
deterministic reality from the eternal past to the eternal future. What
does that tell you about Einstein's adamant stance against quantum
physicists' assertion that nature is governed partially by chance? This
gives new meaning to the often quoted "God does not play dice with the
universe". Heck, it wouldn't matter whether God played dice or not. The
outcome is already determined zillions of years in advance! Does anyone
want to live in Einstein's spacetime driven reality? I don't. It's a
depressing reality, to say the least. Spacetime is so much bunk!
Best regards,
Louis Savain
--
I reserve the right to change my opinion in the face of strong evidence to
the contrary. By all means, do contradict me.
Matthew J. McIrvin
> This is one of the most damaging pieces of information I know of that
> one can use against the idea of spacetime. Spacetime requires a 100%
> deterministic reality from the eternal past to the eternal future. What
> does that tell you about Einstein's adamant stance against quantum
> physicists' assertion that nature is governed partially by chance? This
> gives new meaning to the often quoted "God does not play dice with the
> universe". Heck, it wouldn't matter whether God played dice or not. The
> outcome is already determined zillions of years in advance! Does anyone
> want to live in Einstein's spacetime driven reality? I don't. It's a
> depressing reality, to say the least. Spacetime is so much bunk!
Yes, it's true-- the curvature of general-relativistic spacetime can only
be coupled to matter if that matter, itself, moves in a completely
deterministic manner. And this is a big hole in general relativity.
If *that* is your objection to general relativity, then why do you
consider John Baez an adversary? This is precisely why *he* doesn't
believe in general relativity, and he's said so many times (read the
"quantum bowling ball" thread for a recent example of this). Why do you
think he's working on quantum gravity, otherwise?
No physicist in the world-- at least no physicist I know of-- considers
general relativity anything more than a classical (that is, non-quantum)
approximation to the true dynamics of gravitation. And spacetime probably
*isn't* anything like the smooth manifold described by GR, on a
fundamental level.
--
Matt McIrvin http://world.std.com/~mmcirvin/
--
Nntp-Posting-Host: world.std.com
Path: mmcirvin
Date: Sat, 30 Mar 1996 02:41:04 -0500
From: mmci...@world.std.com (Matt McIrvin)
LBsys
mmci...@world.std.com (Matthew J. McIrvin) schreibt:
>Yes, it's true-- the curvature of general-relativistic spacetime can only
>be coupled to matter if that matter, itself, moves in a completely
>deterministic manner. And this is a big hole in general relativity.
Could that 'hole' be explained to a layman in simple words, or say a nice
picture? Is there a gap between the certainty of big number trials (i.e.
determinism) and the uncertainty of the single event?
Lorenz Borsche (FRG)
Dubium sapientiae initium. [Descartes]
Vanesch P.
: Im Artikel <mmcirvin-190...@news.std.com>,
: mmci...@world.std.com (Matthew J. McIrvin) schreibt:
: >Yes, it's true-- the curvature of general-relativistic spacetime can only
: >be coupled to matter if that matter, itself, moves in a completely
: >deterministic manner. And this is a big hole in general relativity.
: Could that 'hole' be explained to a layman in simple words, or say a nice
: picture? Is there a gap between the certainty of big number trials (i.e.
: determinism) and the uncertainty of the single event?
I'll give this one a try. General Relativity is no exception to other "classical"
theories, so it is not necessary to delve into the issues of warped spacetime
to understand it.
A classical theory (be it newtonian mechanics, fluid dynamics, continuum mechanics,
electromagnetism etc...) gives you usually a theoretical frame and some "input/output"
handles towards matter. I will try to make clear what I mean:
Take electromagnetism. You have the theoretical frame, with the E and B fields,
the Maxwell equations and the Lorenz (-: force. So you would think you have it
all. WRONG ! In the maxwell eqs, there are 2 terms, the charge density and the
current density, which are EXTERNAL. Consider them the INPUT of the theory.
It is determined by the motion of matter. On the other hand there is the Lorentz
force: it couples to matter, and can be considered as the OUTPUT of the theory.
In order to get a closed mathematical problem (meaning you can call your maths
collegue and ask him to solve it) you need to attribute something extra. It is
how matter decides to take the output of the theory and respond to it in respect.
In our case, the Lorentz force is taken to influence matter, and a certain
prescription (called a BEHAVIOURAL EQUATION) that describes the, eh, behaviour
of matter is used to tell you what will be the resulting charge and current densities.
(which are then the input of the theory again, and the circle is closed).
This behavioural stuff can be several things: it can be simply Newton's equation
F = m.a if we are only considering one, free, charged particle. Even there, there
is an extra input: the mass of the particle. But in macroscopic systems, the
behavioural equation can be given by Ohm's law, or a more complicated variation of it,
or something else (like a behavioural eq. for a plasma).
Other example: continuum mechanics. There are 2 fields of importance there:
the field of the displacements of the infinitesimal matter elements, and the field
of the tensions in matter. One set of relations is given from first principles
by applying Newton's law to the infinitesimal matter elements. But again, this
is not a closed system of equations.
Another set of (again, behavioural equations) is needed to describe the response
of matter (in the form of displacements) when subject to certain tensions.
Here it is a bit harder to separate "input" from "output".
All these behavioural equations are or completely empirical (such as Ohm's law),
or they are the result of a theory of matter, but they are not part of the
classical theory under consideration. And except for plasma physics, these
"theories of matter" need a quantum description of some kind.
As my professor of materials science used to say: "Without behavioural equations
and the empirism that goes with it, it wouldn't matter if we would build a bridge
out of steel or out of butter."
Back to GR (which is also a classical theory).
There are 2 elements at play: the Einstein tensor (which is just a very
complicated way of coding the metric of spacetime) and the stress-energy
tensor. The "first principles" part of GR is the equality of both, which
is just Einstein's equation.
It tells you that IF YOU KNOW the "stress-energy" of matter, eg, how matter
is moving, then you know the Einstein tensor (and hence, the metric, and
hence how spacetime is curved).
But how do you get the stress-energy tensor ?
Well, that is, again, THE BEHAVIOURAL PART of our classical theory and
is not given by GR itself (just as the elasticity of butter or steel isn't
given by continuum mechanics, but by an empirical equation).
It has to give you the opposite relationship: given a certain metric,
what is the stress-energy tensor.
It will depend on how matter will behave under influence of gravity. If there
would be no other interaction in the universe, then every particle would follow
a geodesic, and the stress-energy tensor would be easily derivable from
this knowledge (and the kind of particle). But if there are many things going
on, like nuclear interactions, electromagnetic interactions etc... things
get more complicated.
This is not a particular problem of GR. It is the problem of every "partial"
theory in general, and every classical theory especially.
cheers,
Patrick.
Who is trying out his newsserver in Brussels, cuz the one in DESY has given
up apparently.
me...@cars3.uchicago.edu
>Im Artikel <mmcirvin-190...@news.std.com>,
>mmci...@world.std.com (Matthew J. McIrvin) schreibt:
>
>>Yes, it's true-- the curvature of general-relativistic spacetime can only
>>be coupled to matter if that matter, itself, moves in a completely
>>deterministic manner. And this is a big hole in general relativity.
>
>Could that 'hole' be explained to a layman in simple words, or say a nice
>picture? Is there a gap between the certainty of big number trials (i.e.
>determinism) and the uncertainty of the single event?
>
in classical physics too. True, it is not curved and the time and
space parts are decoupled (meaning that no transformation mixes time
and space). Nevertheless it is there and classical machanics works
very well, quite oblivious to quantum effects till you get to very
small scales. So fine, we know by know that classical mechanics is
just an approximation, not the real thing. But within a broad realm
it is an excellent approximation.
The proper analogy here is optics. We've geometrical optics where we
talk about "rays" and which is indistinguishable from particle
dynamics and we've wave optics which takes into account the fact that
light is a wave. Now, in principle ray optics is "wrong". However it
works extremely well till you start considering features of dimensions
comparable to wavelength. The shorter the wavelength the farther you
can go before wave effects become noticable. And the wavelengths
associated with QM are very short indeed.
So I would rephrase Matthew's statement above as follows:
___________
A theory in which the curvature of spacetime is fully coupled to
matter can be exact only if this matter moves in a completely
deterministic manner. Else it is to be considered an approximation
which may, at some point, be replaced by a more exact theory.
__________
So, IMO there is no "big hole" unless somebody expects physical
theories to be perfect (I don't). What's there is an indication that
the two most successful theories we've nowadays, QM and GR, are in
some respects incompatible and either one or both will have to be
modified before they can be smoothly combined.
Mati Meron | "When you argue with a fool,
me...@cars.uchicago.edu | chances are he is doing just the same"
john baez
>No physicist in the world-- at least no physicist I know of-- considers
>general relativity anything more than a classical (that is, non-quantum)
>approximation to the true dynamics of gravitation. And spacetime probably
>*isn't* anything like the smooth manifold described by GR, on a
>fundamental level.
Exactly. The main reason I am interested in quantum gravity is that it
is bound to completely shatter the picture of spacetime given to us by
previous theories: Aristotelian and Newtonian physics, special and
general relativity. But of course one needs to understand general
relativity, even though it's not "the ultimate truth", if one is going
to have any chance to understand quantum gravity. So I spend a lot of
time trying to understand (and explain) general relativity, even though
it's false!
In fact, for all the theories of physics we have, we either know they
are false, because they are incomplete (general relativity and the
Standard Model), or we don't know they are true, because they make no
new experimentally verified predictions (e.g. string theory).
Nonetheless some of these theories are incredibly successful, so one
must learn them to make any progress.
me...@cars3.uchicago.edu
"incomplete" or "inexact" instead of "false", and that's for two
reasons. First, with all the laymen around going out of their way to
misinterpret and misquote all they hear, I would hate the idea to keep
explaining why do we use false theories. Second, the usage of "false"
implies indirectly that somewhere out there there is a "true" theory,
while in fact the most we can hope for is a theory which is "not known
to be incomplete"
LBsys
: mmci...@world.std.com (Matthew J. McIrvin) schreibt:
: >Yes, it's true-- the curvature of general-relativistic spacetime can
only
: >be coupled to matter if that matter, itself, moves in a completely
: >deterministic manner. And this is a big hole in general relativity.
: Could that 'hole' be explained to a layman in simple words?
Patrick and Mati answered as follows:
pvan...@vub.ac.be (Vanesch P.) schreibt:
>It will depend on how matter will behave under influence of gravity. If
>there would be no other interaction in the universe, then every particle
>would follow a geodesic, and the stress-energy tensor would be easily
>derivable from this knowledge (and the kind of particle). But if there
are
>many things going on, like nuclear interactions, electromagnetic
>interactions etc... things get more complicated.
>
>This is not a particular problem of GR. It is the problem of every
"partial"
>theory in general, and every classical theory especially.
me...@cars3.uchicago.edu schreibt:
__________
>A theory in which the curvature of spacetime is fully coupled to
>matter can be exact only if this matter moves in a completely
>deterministic manner. Else it is to be considered an approximation
>which may, at some point, be replaced by a more exact theory.
__________
>So, IMO there is no "big hole" unless somebody expects physical
>theories to be perfect (I don't). What's there is an indication that
>the two most successful theories we've nowadays, QM and GR, are in
>some respects incompatible and either one or both will have to be
>modified before they can be smoothly combined.
Thanks, Patrick and Mati, it's good to know, that the GR/QT community
agrees even upon uncertainties and contradictions of their shared
theories.
What does a layman make out of your words? When you're talking of matter,
you obviously seem to have both in mind at the same time: the single
particle, whichs behaviour is described by QT as well as for example JB's
brick tumbling through space (BTW: where's the triple point for bricks
:-?), thus bodies.
In 'classic' systems, that's what I get from both of you, we have
determinism, so as GR tells how gravity (of matter) is bending space-time,
thus space-time is forming gravity, which in reverse... and so forth,
which means: we very well know, where good old earth will be in about 1000
years. At least that's how it seems.
Now QT can't even tell us, where a single particle will be next (here,
there, everywhere). We might get a probability, and that's about it. Oh,
it cannot even tell us, if its *matter* we are talking about, QT just
waves us a gentle 'hello' while passing :-).
Now as GR tells us exactly, how the future should look like, whereas QT
says "It might look like this, but don't ever think of getting closer to
it", physicist are confused. Is that so? Is that the problem? Is it, b/c
in QT there is no influence of gravity to be calculated - as no one knows
how? And as we can't measure it, so we have not even the faintes idea what
the mathematics could look like?
Now to enlighten me further:
Lurking at the GR tutorial I get the impression that it is far from being
easy looking only at a simple flat spacetime system. When someone tried to
add a solar system with just one sun and one planet, JB cried 'Fire!' as
the maths would really get complicated. Now regarding a whole lot off side
effects (more planets, moons, asteroid belts, comets in and out), I
'feel', your maths describing it would blow up to an extent that even
Crays won't handle, not to speak of the influence of interstellar matter,
our own or other galaxies. We may end up with Laplaces demon of another
sort: Although the axioma are simple, the model describing reality would
be far to complex, then to ever being resolved, and one could even say, it
cannot be resolved, so the future again is open. Not in every direction,
but this is not at all what QT says: Behind the slit, I cannot tell where
the photon will go this time, but it follows a certain pattern. As the way
backwards is not included, I might very well say: I don't know where it's
going for certain, but certainly not back at me.
Now for QT: Yes, we can't tell about the single event, but we can tell
about lot's of events. With a few hundred particles, our incertainty is
gone and made room for statistical probability. It's like tossing a coin:
although you just cannot predict the single throw, you can predict 0.5
times heads, when throwing 1 million times and summing it up to one. So QT
is uncertain for the single throw, but very precise for big numbers. As GR
is very certain for simple flat or two body systems (each body containg
big numbers of particles) but looses precisesness the more bodies are in
the game. It's seems to represent both ends of the balance. It's looks
like a macro/micro problem. Regarding the universe the spin of an electron
is meaningless (Pauli forgive me), and regarding a photon, spacetime may
have an effect on the obserever, watching his clock, but thats highly
theoretical. A pion doesn't care for the deterministic predictions of GR -
it decays, when it's probable time is up. I wouldn't try to repair an
ocean liner with a screw driver made for my wrist watch. I wouldn't try to
repair my wrist watch with a screw made for an ocean liner. Describing the
universe with QT is as useless as applying the laws of gravity on a single
particle. That's all I can see there is.
This sounds to be far to easy. Obviously I haven't been able to catch the
real twist. So I have to ask you to try to enlighten me further. Will you?
Thanks in advance.
LBsys
schreibt:
>Exactly. The main reason I am interested in quantum gravity is that it
>is bound to completely shatter the picture of spacetime given to us by
>previous theories: Aristotelian and Newtonian physics, special and
>general relativity. But of course one needs to understand general
>relativity, even though it's not "the ultimate truth", if one is going
>to have any chance to understand quantum gravity. So I spend a lot of
>time trying to understand (and explain) general relativity, even though
>it's false!
Ok, I'll buy that and don't misinterprete false as being false - just
incomplete (as Mati has correctly laid out)!
Newtons mechanics wrt the above interpretation were just incomplete,
right? It was sort of a special case of GR. GR had to add a factor for
high (relative) velocities - which made the old formula less elegant. But
anyway cancels out in certain (Newtonian) cases.
Now shouldn't we look forward to a quantum gravity theory, which includes
GR as 'a special case' ?
Instead of something that "is bound to completely shatter the picture of
spacetime given to us by previous theories"
(... I always had a great like and infallible feeling for special cases in
school maths: often found a simple solution instead of the general one,
b/c the teacher once again had choosen a neatly formed cube or a
rectangular triangle or the like - drove them mad :-).
I would suspect the quantum gravity to evolve as a rather minor
'correction factor' in reality. Don't get me wrong: All I'm saying is that
counted out on a big scale, we might still use GR formulas like we do now
use Newtonion eqns, when we expect GR effects to be neglectable. Or am I
thinking complete in the wrong direction?
me...@cars3.uchicago.edu
>Im Artikel <4l8ud9$9...@guitar.ucr.edu>, ba...@guitar.ucr.edu (john baez)
>schreibt:
>
>>Exactly. The main reason I am interested in quantum gravity is that it
>>is bound to completely shatter the picture of spacetime given to us by
>>previous theories: Aristotelian and Newtonian physics, special and
>>general relativity. But of course one needs to understand general
>>relativity, even though it's not "the ultimate truth", if one is going
>>to have any chance to understand quantum gravity. So I spend a lot of
>>time trying to understand (and explain) general relativity, even though
>>it's false!
>
>Ok, I'll buy that and don't misinterprete false as being false - just
>incomplete (as Mati has correctly laid out)!
>Newtons mechanics wrt the above interpretation were just incomplete,
>right? It was sort of a special case of GR. GR had to add a factor for
>high (relative) velocities - which made the old formula less elegant. But
>anyway cancels out in certain (Newtonian) cases.
>Now shouldn't we look forward to a quantum gravity theory, which includes
>GR as 'a special case' ?
>Instead of something that "is bound to completely shatter the picture of
>spacetime given to us by previous theories"
>
presented as "completely shattering the previous picture" but when the
dust clears it'll turn out that it is just a more general thing, the
previous theories being special cases of. As it should be since
obviously it must asymptotically reduce to the previous theories in
the reange of parameters within which they work.
>
>I would suspect the quantum gravity to evolve as a rather minor
>'correction factor' in reality. Don't get me wrong: All I'm saying is that
>counted out on a big scale, we might still use GR formulas like we do now
>use Newtonion eqns, when we expect GR effects to be neglectable. Or am I
>thinking complete in the wrong direction?
No, I think that's the right direction. If quntum gravity would make a
big difference, "in reality", we would observe by now some
discrepancies between the predictions of QM or GR (or both) and
reality.
gl...@gnn.com
In article <4l8ud9$9...@guitar.ucr.edu> john baez wrote:
>>No physicist in the world-- at least no physicist I know of--
>>considers general relativity anything more than a classical (that
> Exactly. The main reason I am interested in quantum gravity is
>that it is bound to completely shatter the picture of spacetime
>given to us by previous theories: Aristotelian and Newtonian
>physics, special and general relativity. But of course one needs
>to understand general relativity, even though it's not "the
>ultimate truth", if one is going to have any chance to understand
>quantum gravity. So I spend a lot of time trying to understand
Why do you want to understand, much less "expain", a false
theory. BTW, thanks for announcing your admittedly expert opinion
that "it's false". Good for you!
Glird http://members.gnn.com/glird/reality.htm
SavainL
>In article <4l8ud9$9...@guitar.ucr.edu>, ba...@guitar.ucr.edu (john baez)
>writes:
>>In article <mmcirvin-190...@news.std.com>
>>mci...@world.std.com (Matthew J. McIrvin) writes:
>>
>>Exactly. The main reason I am interested in quantum gravity is that
>>it is bound to completely shatter the picture of spacetime given to us
>>by previous theories: Aristotelian and Newtonian physics, special and
>>general relativity. But of course one needs to understand general
>>relativity, even though it's not "the ultimate truth", if one is going
>>to have any chance to understand quantum gravity.
Balderdash! No one needs to wait for quantum gravity to completely
shatter the picture of spacetime. It is shattered now! It has miserably
collapsed under the weight of its own stupidity. And BTW, there's no need
to bring yet another convoluted theory into physics. There's only one
way in which all forces are mediated, including the gravitational force,
and that is through the exchange of particles, i.e., through particle
interactions. What's wrong with using a proven concept?
>> So I spend a lot of
>>time trying to understand (and explain) general relativity, even
>>though it's false!
>>
>>In fact, for all the theories of physics we have, we either know they
>>are false, because they are incomplete (general relativity and the
>>Standard Model), or we don't know they are true, because they make no
>>new experimentally verified predictions (e.g. string theory).
>>Nonetheless some of these theories are incredibly successful, so one
>>must learn them to make any progress.
>>
>I don't like to nitpick but I would seriously suggest using the term
>"incomplete" or "inexact" instead of "false", and that's for two
>reasons. First, with all the laymen around going out of their way to
>misinterpret and misquote all they hear, I would hate the idea to keep
>explaining why do we use false theories.
This is incredible. I grant you that I would not go as far as saying
that GR is false due to it being based on spacetime, for the same reason
that I would not as far as to say that Newtonian physics is false because
it postulates action at a distance. But at least Newton did not come out
and say that there is in fact action at a distance, only that massive
bodies behave *as if* there were action at a distance. Newton is to be
commended for his caution. Spacetime, on the other hand, is *openly*
given and taught all over the world as *the* cause of motion and gravity.
The truth is that the idea of spacetime curvature on which GR is very
much based is indeed 100% false. Saying that it is "incomplete" is like
saying that the flat earth theory is not false but merely "incomplete".
What nonsense! Spacetime is stupidity at its worst! Why? Because it did
not come from a bunch of pseudo-scientists and amateur physicists; it
came from the creme de la creme, the Nobel prize winners of physics. For
you guys to try to rationalize an obvious nonsense by using ambiguous
language like "incomplete" does not strike me as particularly courageous.
Baez is right on in this respect. Spacetime *is* false.
Why do physicists continue to perpetuate such a stupid concept by
claiming it's incomplete? Have some strength and go to your students and
tell them the truth: "Hey guys and gals, you know this spacetime thing
we've been telling you about all these years, yeah, this awesomely
beautiful thing that is responsible for gravity, black holes time travel
and all that good stuff, well it's completely bunk! Surpraaaise!" Now,
that would be true courage. Guess what! I'm not holding my breath
waiting for that to happen!
> Second, the usage of "false"
>implies indirectly that somewhere out there there is a "true" theory,
>while in fact the most we can hope for is a theory which is "not known
>to be incomplete"
No amount of rationalizing is going to dig spacetime physicists out this
absurd hole they got themselves into. We don't judge theories by
comparing them to "true" theories. We judge them by comparing them with
reality. In this regard, spacetime is one of the most unrealistic
theories of them all because it has no basis in reality. It was wrong
right out of the box! Heck, I'd say the flat earth concept has more merit
than spacetime as we don't expect any better coming from non-scientists.
Why have physicists been sitting on this nonsense for so long? Why have
they not informed their students that there's a major logical flaw in the
idea of spacetime that renders it completely useless as a basis for
reality? Why is it taking an outsider to bring this monumental flaw into
the open? What are you afraid of? And don't tell me you've been saying
the same thing that I'm saying all along because you haven't. No one's
going to believe it. Gosh! When I think that a whole generation of young
people have been brainwashed into believing in this spacetime manifold
absurdity! What a waste!
LBsys
(I post it with his consent and b/c it really gave me hints, what the
whole debate is about and why JB is so important, maybe other laymen get
enlightened too. Further enlightments can be found in the thread "When GR
weds QM, what are likely offspring"?):
> Thanks, Patrick and Mati, it's good to know, that the GR/QT community
agrees
> even upon uncertainties and contradictions of their shared theories.
Eh, ahum. Yes, of course we know that physics isn't finished yet !
It is one of the big open questions: how to "quantize" GR. John
Baez is one of the "happy few" working on that problem. He hasn't
found it yet. It is called "job protection" :-)
>
> What does a layman make out of your words? When you're talking of
matter, you
> obviously seems to to have both in mind at the same time: the single
> particle, which's behaviour is described by QT as well as for example
JB's
> brick tumbling through space (BTW: where's the triple point for bricks
:-?),
> thus bodies.
>
> In 'classic' systems, that's what I get from both of you, we have
> determinism, so as GR tells how matter is bending space-time, thus
space-time
> is forming matter, which in reverse... and so forth, which means: we
very
> well know, where good old earth will be in about 1000 years. At least
that's
> how it seems.
in principle. Whether we can actually do the calculation is another
story.
> Now QT can't even tell us, where a single particle will be next (here,
there,
> everywhere). We might get a probability, and that's about it. Oh, it
cannot
> even tell us, if its *matter* we are talking about, QT just waves us a
gentle
> 'hello' while passing :-).
Yes. And people tried almost everything to avoid coming to that
conclusion. But apparently there is no escape :)
> Now as GR tells us exactly, how the future should look like, whereas QT
says
> "It might look like this, but don't ever think of getting closer to it",
> physicist are confused. Is that so? Is that the problem?
More or less. GR is still a "classical theory", like Newtonian
mechanics is, and like Maxwellian electromagnetism is. Now, QT
gives us a rule how to make a quantum theory out of a classical
theory. It works for electromagnetism ==> QED, and it works for
newtonian mechanics ==> non-relativistic quantum mechanics, which
is used all over in chemistry, lasers, solid state physics, transistors
etc...
But it doesn't work for GR. GR doesn't have the right structure
to apply the "make it quantum" rule of Quantum Theory.
So that's a big puzzle.
> Is it, b/c in QT
> there is no influence of gravity to be calculated - as no one knows how?
And
> as we can't measure it, so we have not even the faintes idea what the
> mathematics could look like?
The fact that we don't measure quantum gravity effects because they're
way too weak is also a problem: we have no clue !
> Now to enlighten me further:
> Following the GR tutorial I get the impression that it is far from being
easy
> looking at a simple flat spacetime system. When someone tried to add a
solar
> system with just one sun and one planet, JB cried 'Fire!' as the maths
would
> really get complicated. Now regarding a whole lot off side effects (more
> planets, moons, asteroid belts, comets in and out), I 'feel', your maths
> describing it would blow up to an extent that even Crays won't handle,
not to
> speak of the influence of interstellar matter, our own or other
galaxies. We
> may end up with Laplaces demon of another sort: Although the axioma are
> simple, the model describing reality is far to complex, then to ever
being
> solved, and one could even say, it cannot be solved, so the future again
is
> open.
Yes, complexity is still with us. We may have the equations, but don't
know how to find the solutions. The last bit is conveniently called
a mathematical problem but it is there nevertheless.
Even more. The stuff I'm working on (but as - unfortunately - an
experimentalist), is Quantum Chromodynamics. There, we have the
theory, the equations, and we don't even know how to solve a
SIMPLE problem. (well, we know some aspects, but we don't know
any exact solution, and we don't even know if our approximations
are approximations !)
> Not in every direction, but this is not at all what QT says: Behind the
> slit, I cannot tell where the photon will go this time, but it follows a
> certain pattern. As the way backwards is not included, I might very well
say:
> I don't know where it's going for certain, but certainly not back at me.
Ok, but for that you don't need a lot of theory :)
> Now for QT: Yes, we can't tell about the single event, but we can tell
about
> lot's of events. With a few hundred particles, our incertainty is gone
and
> made room for statistical probability. It's like tossing a coin:
although you
> just cannot predict the single throw, you can predict 0.5 times heads,
when
> throwing 1 million times and summing it up to one. So QT is uncertain
for the
> single throw, but very precise for big numbers. As GR is very certain
for
> simple flat or two body systems (each body containg big numbers of
particles)
> but looses precisesness the more bodies are in the game. It's seems to
> represent both ends of the balance.
Yes, that is the nice thing. All this "incompleteness of GR / QT" stuff
is only a matter of principle. There were QT matters, GR doesn't play
a role at all and vice versa. It is only in EXTREMELY strange and weird
places (like the first billionth of second of the big bang - or tiny
black holes) that both of them play a role. These weird places are
"at the Planck scale".
If you're a practical guy, you say: GREAT ! So we actually know
everything (in principle) except for these weird places we'll never
study anyhow.
If you are a philosopher, you say SHIT ! We have a principal
inconsistency between GR and QT, and no experiment in the coming
500 years (rough guess :) is going to address these matters, so
we will not know.
And if you're a crackpot, you silently solve the problem and you
tell the world that TIME IS BOILING EGG :-)
It's looks like a macro/micro problem.
> Regarding the universe the spin of an electron is meaningless (Pauli
forgive
> me), and regarding a photon, spacetime may have an effect on the
obserever,
> watching his clock, but thats highly theoretical. A pion doesn't care
for the
> deterministic predictions of GR - it decays, when it's probable time is
up. I
> wouldn't try to repair an ocean liner with a screw driver made for my
wrist
> watch. I wouldn't try to repair my wrist watch with a screw made for an
ocean
> liner. Describing the universe with QT is as useless as applying the
laws of
> gravity on a single particle. That's all I can see there is.
That is the "practical guy viewpoint". The rest is indeed just a matter
of taste. I more or less adopt the same philosophy, because it must be
way frustrating to FINALLY UNIFY GR AND QT, and none of your new
predictions will be verified in the coming 500 years (if ever). We
actually have (a few thousand) candidate unifications: that's what
string theory is all about. But the people who work on that NOW will
never see it confirmed or rejected. Must be a pretty hard thing to
swallow I guess....
Of course, when I say this to a string theorist, he quite rightly
corrects me: How can you know ? Right, it MIGHT be that some very
accessible effect is predicted only by string theory. But I don't
think so !
> Obviously I haven't been able to catch the real twist. So I have to ask
you
> to try to enlighten me further. Will you? Thanks in advance.
>
On the contrary, I think you have a rather good view on it.
cheers,
Patrick.
PS: I won't post this again, I just mailed it to you. You can post it
if you want to, but here, both of my newsservers are utterly confused
(the one in Brussels and the one in DESY).
SavainL
In article <4lbi44$q...@news-e2c.gnn.com>, gl...@gnn.com () writes:
>In article <4l8ud9$9...@guitar.ucr.edu> john baez wrote:
>>>No physicist in the world-- at least no physicist I know of--
>>>considers general relativity anything more than a classical (that
>>>is, non-quantum) approximation ...
>> Exactly. The main reason I am interested in quantum gravity is
>>that it is bound to completely shatter the picture of spacetime
>>given to us by previous theories: Aristotelian and Newtonian
>>physics, special and general relativity. But of course one needs
>>to understand general relativity, even though it's not "the
>>ultimate truth", if one is going to have any chance to understand
>>quantum gravity. So I spend a lot of time trying to understand
>>(and explain) general relativity, even though I know it's false.
> Why do you want to understand, much less "expain", a false
>theory. BTW, thanks for announcing your admittedly expert opinion
>that "it's false". Good for you!
John Baez is a strange guy. I feel like I'm riding a roller-coaster
whenever I read Baez's messages. He goes from talking from both sides of
his mouth to showing amazing courage and wit. I realize I'm not in his
shoes and I don't envy his position. But I do commend him for his courage
in this case.
Jim Conner
> Why do you want to understand, much less "expain", a false
> theory. BTW, thanks for announcing your admittedly expert opinion
> that "it's false". Good for you!
Sheesh. Get a grip, buddy. Do you think that *any* theory provides a
perfect description of Nature over all ranges of energy, all time scales,
etc.? The best that we can hope for is continually improving
approximations to what Nature is really doing. Some of these
approximations are very good, but you can bet that someday someone will
make a measurement or perform an experiment that shows one (or more) of
these approximations to be inadequate.
*All* of our theories are false, in the sense that they do not perfectly
describe the workings of the world in all conditions. This does not take
away from their usefulness over limited ranges, or make it any less proper
to teach and explain them to others.
Jim Conner
jc...@cornell.edu
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john baez
>Im Artikel <4l8ud9$9...@guitar.ucr.edu>, ba...@guitar.ucr.edu (john baez)
>schreibt:
>Now shouldn't we look forward to a quantum gravity theory, which includes
>GR as 'a special case' ?
>Instead of something that "is bound to completely shatter the picture of
>spacetime given to us by previous theories"
Of course quantum gravity should reduce to general relativity in most
circumstances, and in many circumstances provide only miniscule
correction terms. General relativity will remain incredibly useful for
many problems. But nonetheless, quantum gravity is bound to completely
shatter the picture of spacetime --- the worldview --- given to us by
previous theories.
It's just like what general relativity did to Newtonian gravity. In our
solar system, the general-relativistic corrections to Newtonian physics
are very small. Newtonian physics remains a extraordinarily useful
framework for dealing with many physics problems. It is also very
beautiful. So it will always be well worth mastering. But: even if
spacetime is only very SLIGHTLY curved, the fact that it's curved AT ALL
would completely blow the mind of anyone who grew up on the certainties
of Newtonian physics, one of which is Euclidean geometry.
It's almost as if someone said "Oh, by the way, 1 + 1 doesn't exactly
equal 2, but don't get upset: it's very, very close." Something
can be mindblowing, and conceptually very important, even if in most
practical situations its effects are very small. General relativity
radically altered our picture of what spacetime is like.
>I would suspect the quantum gravity to evolve as a rather minor
>'correction factor' in reality.
In most situations, probably. It might make a huge difference for what
happens at the singularity of a black hole, or at the very beginning of
the universe. Thus it might drastically change our theories as to the
origin and fate of the universe. There is a lot of work being done
along these lines already. But what matters to me, personally, most of
all, is how it will change our understanding of spacetime.
Tom Potter
> NOTHING MOVES IN SPACETIME!!!
> The spacetime concept was created because physicists believed that time
>could be viewed as one of the 4 dimensions of reality. The problem with
>making time a dimension is that it renders spacetime completely
>motionless. I mean dead, changeless, unchangeable.
In order to resolve an assertion,
one must establish a dichotomy,
which directly impacts the primary POINT of the assertion.
Savain made a specific assertion, which has NOT been addressed.
There has been a lot of hand waving, but no one has established a
dichotomy upon the SPECIFIC POINT of the assertion.
That is:
If "matter" exists at some x,y,z,t,
what does it change in reference to?
It seem to me that we are back to Zeno.
I assert that time-space and matter are just different expressions of
the same thing, and they all are just cycles and cycle ratios.
Kepler discovered that time-space and "matter" was the same thing
and expressed as: M(A) = distance(B)^3 / time^2
Einstein discovered that time and space was the same thing
and expressed as: x^2 + y^2 + z^2 = (ct)^2
But I think he should have expressed it as:
(x/c)^2 + (y/c)^2 + (z/c)^2 = t^2
which expresses space as time, which is closer to reality.
And, of course, I assert that time is simply a ratio of cycles:
time(X) = cycles(reference) / cycles(X)
Tom Potter http://pobox/~tdp
me...@cars3.uchicago.edu
>I asked:
Stuff snipped (reluctantly, but its getting long)...
I think that you got most, if not all, of the real twist. It is a
matter of looking at physics at two different levels. One is the
profound level of "understanding how the universe works" the other
isthe down to earth "OK, now given this situation, what's going to
happen". And both are important.
So we have various "incomplete" theories which work in a limited range
and work extremely good over there. They are here to stay. Engineers
didn't junk Newtonian mechanics and started using QM or relativity in
their calculations since, as you observe, the answers given by
Newtonian mechanics are perfectly good in their realm of operation and
the calculations are way simpler. Part of the art of applying science
to the real world is not to include everything but to include all
that's relevant.
At the same time we would like to join these "partial theories"
together. There is this human urge to understand what's going on and,
on the practical side, when you get a more general picture you may
ntice things that were overlooked before. So that's fine, but we
shouldn't think in terms of "we'll get an ultimate theory and apply it
to everything". I'm surethat even having a theory that combines all
of our knowledge, we'll then use it to derive simple approximations
valid for the various issues we care about and use these
approximations. Else, using your analogy, we'll end up with one
screwdriver which we try to use on everything and which is cumbersome
in all its applications.
SavainL
writes:
>In article <4lamn9$o...@newsbf02.news.aol.com>, lb...@aol.com (LBsys)
>writes:
>>[...]
>>Now shouldn't we look forward to a quantum gravity theory, which
>>includes GR as 'a special case' ?
>>Instead of something that "is bound to completely shatter the picture
>of spacetime given to us by previous theories"
>
>Judging by past experience we'll get something which will be first
>presented as "completely shattering the previous picture" but when the
>dust clears it'll turn out that it is just a more general thing, the
>previous theories being special cases of. As it should be since
>obviously it must asymptotically reduce to the previous theories in
>the reange of parameters within which they work.
It is true that a new theory of gravity would have to make predictions
that are least as good as GR or better. Saying that it would have to
"asymptotically reduce to" GR is misleading. Only the predictions need to
be as good or better than the old ones, not the theory. The new theory in
this case will completely replace the old one. It does not need to reduce
to GR since GR is based on the concept of spacetime, and spacetime, as we
should all know by now, is complete 100% nonsense!
Oz
Conner <jc...@cornell.edu> writes
>
>*All* of our theories are false, in the sense that they do not perfectly
>describe the workings of the world in all conditions. This does not take
>away from their usefulness over limited ranges,
As any artillery man or astronaut will readily confirm.
-------------------------------
'Oz "When I knew little, all was certain. The more I learnt,
the less sure I was. Is this the uncertainty principle?"
Keith Stein
writes
> GR is based on the concept of spacetime,
> and spacetime,
> as we
>should all
> know
> by now,
> is complete 100% nonsense!
>
>Best regards,
>
>Louis Savain
i don't understand.
Are you saying that
space is 100 % nonsense
and
time is 100 % nonsense ? ?
or
are you just saying
GR is 100 % nonsense ?
which is fine
if you just meant that!
--
Keith Stein
ale2
In article <4lbi44$q...@news-e2c.gnn.com>
gl...@gnn.com () writes:
>
stuff cut
> Why do you want to understand, much less "expain", a false
> theory. BTW, thanks for announcing your admittedly expert opinion
> that "it's false". Good for you!
the following has at best a monetary value of 0.02$ on a good day.
one reason i might want to understand GR
of all that we observe (science) we try to come up with theories which
make sense of what we observe. To me it seems GR does a pretty good job
of making sense of some of what we observe. To me then the structure of
GR (and most of conventional physics) gives a really strong clue to
some deeper model.
You don't have to marry her (GR), you could just be friends, get to
know her, who knows what could happen.
ale2
>
> So, IMO there is no "big hole" unless somebody expects physical
> theories to be perfect (I don't). What's there is an indication that
> the two most successful theories we've nowadays, QM and GR, are in
> some respects incompatible and either one or both will have to be
> modified before they can be smoothly combined.
the above grabbed me, if GR is really only an approximation as i take
from the above statement, can we also think of SR as also being only an
approximation and if so in what way?
thanks
john baez
>>In fact, for all the theories of physics we have, we either know they
>>are false, because they are incomplete (general relativity and the
>>Standard Model), or we don't know they are true, because they make no
>>new experimentally verified predictions (e.g. string theory).
>>Nonetheless some of these theories are incredibly successful, so one
>>must learn them to make any progress.
>I don't like to nitpick but I would seriously suggest using the term
>"incomplete" or "inexact" instead of "false", and that's for two
>reasons.
I sympathize with your suggestions, and normally follow them. I just
felt like being a bit provocative. But I don't think I was being
irresponsible, because I carefully explained what I meant.
>First, with all the laymen around going out of their way to
>misinterpret and misquote all they hear, I would hate the idea to keep
>explaining why do we use false theories.
It's not the layfolk who go out of their way to misinterpret things,
it's the fruitcakes. There is really nothing I can do to keep them from
making fools of themselves. These guys could look at a bus schedule
and come to the conclusion that it was the periodic table. So there is
no point in babying them.
I do think it's important not to confuse layfolk. But I don't think my
statement would confuse *them*. If it did, our little exchange here
should clear that up.
>Second, the usage of "false"
>implies indirectly that somewhere out there there is a "true" theory,
>while in fact the most we can hope for is a theory which is "not known
>to be incomplete"
Well, all I meant was that general relativity does not take quantum
mechanics into account, and the Standard Model does not take gravity
into account. This is worse than being "not known to be incomplete".
It's even worse than being "known to be incomplete". It is being
inconsistent with known facts. Nonetheless, these are the most accurate
theories we have! I'm not knocking them in the least. Anyone who wants
to understand physics thoroughly MUST learn these theories, because they
represent the current pinnacle of human accomplishment as far as physics
goes.
In a certain sense, everything we know about the fundamental laws of
physics has been built into these two theories. The fact that these
theories are not consistent with each other simply means we aren't done
understanding physics yet.
Keith Ramsay
In article <4lbii0$2...@newsbf02.news.aol.com>, sav...@aol.com (SavainL) wrote:
|For you guys to try to rationalize an obvious nonsense by using ambiguous
|language like "incomplete" does not strike me as particularly courageous.
I don't remember anybody claiming bravery here....
Spacetime is clearly not "obvious nonsense", so I think you must be
misunderstanding it in some basic way. Spacetime is the set of all
events, past, present and future. Not absurd at all.
I get the impression that you are somehow taking what somebody
has said about spacetime (i.e., talking about events) as
meaning some bizarre notion of future events being out there, already
"given", fated or already present or something. In fact it is just an
unfamiliar (to you) way of talking about events, including future
ones. For instance, the "set of cattle uncle Bob will own in 2025"
refers to things which don't yet exist, but it's perfectly reasonable
to talk about the collection anyway. It is just in the future. The
same holds for parts of spacetime in our future. The events have not
yet occurred, but in physics we may talk about them anyway.
|Baez is right on in this respect. Spacetime *is* false.
He said general relativity and the standard model are "false". I
don't recall him saying spacetime is false.
There are two types of objections here. One is the objection to
teaching hypothetical, theoretical ideas, which are bound someday
to be revised, as if they were simply true. On this we largely
agree. Certainly I agree that GR is bound to be revised as physics
progresses. This is what people are talking about when they say that
the theory is "incomplete". People are not rationalizing about this
here; we're acknowledging your point.
On the other hand, there is your claim that the theory was an awful
theory from the outset, obviously bad, because of some vague
apprehensions about space-time. People are *not* trying to
rationalize this point either, by saying GR is incomplete. It's
not relevant. If the idea were so bad, being incomplete wouldn't
make it any better. Nobody says it would.
We are simply telling you that this "problem" you think GR has,
that other theories do not have, is simply not a problem. You
think you've seen a problem, but you are simply confused. And
apparently somewhat overconfident of your understanding of the
matter. Do you really think the physics community is a bunch
of total idiots?
Keith Ramsay
SavainL
<sth...@sthbrum.demon.co.uk> writes:
>In article <4lcti8$f...@newsbf02.news.aol.com>, SavainL
><sav...@aol.com> writes
>
>> GR is based on the concept of spacetime,
>
>> and spacetime,
>
>> as we
>>should all
>
>> know
>
>> by now,
>
>> is complete 100% nonsense!
>>
>>Best regards,
>>
>>Louis Savain
>
>i don't understand.
>
>Are you saying that
>
> space is 100 % nonsense
In a deep Eleatic sense, it probably is. But in the context of this
discussion, I'll refrain from getting into this philosophical aspect of
it. BTW this was somewhat debated in another thread called "A Particle's
Position: Intrinsic or Extrinsic?"
> and
> time is 100 % nonsense ? ?
Time, viewed as a spatial dimension, is indeed 100% nonsense as I've
pointed out elsewhere. It is unfortunate that physicists and philosophers
have taken to dimensionalizing time.
> or
>
>are you just saying
>
> GR is 100 % nonsense ?
I don't know enough about GR to say one way or another. But since it's
based on spacetime curvature, it probably is 100% nonsense. It may have
been a case where the equations were fitted to observation. I don't know.
I do know from my understanding of calculus that it's relatively easy to
come up with equations that agree partially or wholly with reality. One
can then use these equations to make accurate predictions and then
incorrectly claim that one understands reality. Newton did it (come up
with great equations, that is) and yet it's clear that he had no idea what
was going on at the fundamental level.
>which is fine
> if you just meant that!
It woud bother me a little if it were just that. There's a lot more at
stake than just GR's nonsensical spacetime curvature.
gl...@gnn.com
In article <4le78n$b...@guitar.ucr.edu> john baez wrote:
>Well, all I meant was that general relativity does not take
>quantum mechanics into account, and the Standard Model does not
>take gravity into account. This is worse than being "not known to
>be incomplete". It's even worse than being "known to be
>incomplete". It is being inconsistent with known facts.
> Nonetheless, these are the most accurate theories we have! I'm
>not knocking them in the least.
>Anyone who wants to understand physics thoroughly MUST learn these
>theories, because they represent the current pinnacle of human
>accomplishment as far as physics goes.
Anyone who wants to understand the physical world better learn
physics, too; but he also ought to learn to ignore theoretical
physics.
>In a certain sense, everything we know about the fundamental laws
>of physics has been built into these two theories. The fact that
>these theories are not consistent with each other simply means we
>aren't done understanding physics yet.
Simply means we aren't (even close to) understanding physical
reality yet, John?
Glird http://members.gnn.com/glird/reality.htm
euejin_jeong
There is always a surprise. Who knows GR may be wrong in certain ranges of
physical reality. But I would guess it won't be easy to invalidate until
a few centuries to come. I guess SR has more clear room to improve. Especially in the part of the rest mass. It looks too rigid. There is no flexibility for
accomodation of the potential energy if anyone would like to do. My guess
is that it has all the inconsistencies in QFD concerning the rigidity of of
the coupling constant and the rest mass. Although renormalization scheme patchea little of flaws up in the theory. SUbstracting infinities and making sense
doesn't seem look strange to many physicist especially to those inclined to
the math side. I personally think math is very important in physics but it should never blurr the physical concept. Most of the time we should be able to tell
the magnitude of the physical quantity before calculation. Blind calculation
is the most dangerous practice in physics. One should know what one will get
before doing the calculation. The beauty in physics is that once the conceptual
framework is set, rest of the math is pretty much well defined.
However, recently the trend is reversed, which to me looks like a dangerous
path meaning a lot of waste of time is forseen.
We have much more mundane pebbles to pick. Those pebbles may show us how to
build the gigantic accelerator to test the future theories without too much
hassle. Actually I forsee it. Neutral particle accelerator may be feasible
according to the new theory with unlimited energy in a linac type machine.
Then we have exciting new testable theories and experiment to go along with.
Without a machine to test the new theories, we are not actually doing physics.
We are doing all kinds of speculations. That's all.
Ray Tomes
>Yes, it's true-- the curvature of general-relativistic spacetime can only
>be coupled to matter if that matter, itself, moves in a completely
>deterministic manner. And this is a big hole in general relativity.
Why are you so confident that the universe is not deterministic?
It seems to me that all evidence to the contrary has been found to be
unsubstantiated. The EPR tests do not hold water as evidence.
Is there anything else? On the other side there are results which
show that the supposed randomness of QM does have a deeper order.
-- Ray Tomes -- rto...@kcbbs.gen.nz -- Harmonics Theory --
http://www.vive.com/connect/universe/rt-home.htm
SavainL
Rams...@hermes.bc.edu (Keith Ramsay) writes:
>In article <4lbii0$2...@newsbf02.news.aol.com>, sav...@aol.com
>(SavainL) wrote:
>|For you guys to try to rationalize an obvious nonsense by using
>|ambiguous language like "incomplete" does not strike me as
>|particularly courageous.
>
>I don't remember anybody claiming bravery here....
Forgive me for making a wrong assumption.
>Spacetime is clearly not "obvious nonsense", so I think you must be
>misunderstanding it in some basic way. Spacetime is the set of all
>events, past, present and future. Not absurd at all.
Spacetime is indeed what you say it is. And that's precisely what makes
it absurd. It is an unchanging, motionless set. It forbids uncertainty.
Realities that demand either 100% uncertainty or 100% determinism are
equally absurd. It's like having a world where only 'left' is permitted
and 'right' is forbidden, or vice versa. It's nonsense! If this is not
obvious to you, what's the point of discussing it?
>I get the impression that you are somehow taking what somebody
>has said about spacetime (i.e., talking about events) as
>meaning some bizarre notion of future events being out there, already
>"given", fated or already present or something.
No one's ever told me that. But that's exactly what spacetime means
since nothing can move in spacetime. It's all preset. Are you
questioning this?
> In fact it is just an
>unfamiliar (to you) way of talking about events, including future
>ones.
Physicists teach that everything exists in spacetime. I've been hearing
it and reading about it for a long time. You call it unfamiliar. I call
it nonsense.
> For instance, the "set of cattle uncle Bob will own in 2025"
>refers to things which don't yet exist, but it's perfectly reasonable
>to talk about the collection anyway. It is just in the future. The
>same holds for parts of spacetime in our future. The events have not
>yet occurred, but in physics we may talk about them anyway.
I fail to see the point of this. You say it does not exist (and I
agree) yet most physicists say that not only does it exist, it can be
curved by matter and it can affect the motion of matter. Which is it?
Either it exists or it doesn't. Make up your mind.
>|Baez is right on in this respect. Spacetime *is* false.
>
>He said general relativity and the standard model are "false". I
>don't recall him saying spacetime is false.
Well Baez said this:
>[...] The main reason I am interested in quantum gravity is that it
>is bound to completely shatter the picture of spacetime given to us by
>previous theories: Aristotelian and Newtonian physics, special and
>general relativity.
To me, it sounds very much like he's not happy with spacetime. I was
just agreeing with him there. Are we talking about a different Baez? Or
are you just nitpicking because you don't like what I've been saying about
spacetime?
>There are two types of objections here. One is the objection to
>teaching hypothetical, theoretical ideas, which are bound someday
>to be revised, as if they were simply true. On this we largely
>agree. Certainly I agree that GR is bound to be revised as physics
>progresses. This is what people are talking about when they say that
>the theory is "incomplete". People are not rationalizing about this
>here; we're acknowledging your point.
>On the other hand, there is your claim that the theory was an awful
>theory from the outset, obviously bad, because of some vague
>apprehensions about space-time. People are *not* trying to
>rationalize this point either, by saying GR is incomplete. It's
>not relevant. If the idea were so bad, being incomplete wouldn't
>make it any better. Nobody says it would.
To tell you the truth, I don't really care all that much about GR. The
point of this thread is spacetime. Spacetime is absurd whether or not it
may shatter your world view. If GR is based 100% on the validity of
spacetime, then I would not say that it needs to be revised because it is
simply incomplete. I would say that it needs to be completely *replaced*
by a new theory that is not based on spacetime. Period.
>We are simply telling you that this "problem" you think GR has,
>that other theories do not have, is simply not a problem. You
>think you've seen a problem, but you are simply confused. And
>apparently somewhat overconfident of your understanding of the
>matter.
It's more than a problem. It's a scandal. I've made some specific
objections to spacetime that you have completely ignored and instead you
are confusing the issue by claiming that I don't understand it. That's a
really lame argument, Keith. I could easily say the same about you and I
would probably be right. As I mentioned in another folder, creationists
could claim victory by accusing you of not understanding that the whole
universe was created in 4004 BC.
> Do you really think the physics community is a bunch
>of total idiots?
Well, believe it or not, I'm beginning to seriously ask myself this very
question. I've seen a few things written on sci.physics *by physicists*
that are not too flattering, to say the least. And I can quote chapter
and verse if I have to. You're right though. I would never say that
physicists are total idiots. Many of them certainly do show some signs of
idiocy in certain areas.
But then again, it could be idiocy, fear, pride, vanity, or just plain
mule-headedness. I really don't care. We all suffer from one shortcoming
or another. I'm looking for a few people who can see the absurdity of
spacetime and have a serious discussion about it. If needs be, the
discussion can be carried off line so as not to offend the sensibilities
of some physicists. I say "some" because not all would be offended. I
already know of several physicists who agree with me on spacetime. Or
rather, I should say that I agree with *them* on spacetime. And no, they
are not total idiots. Only partially, just like everyone else.
Oz
writes
>
>In a certain sense, everything we know about the fundamental laws of
>physics has been built into these two theories. The fact that these
>theories are not consistent with each other simply means we aren't done
>understanding physics yet.
Luckily for theoretical Physicists at the 'cutting edge', who would
otherwise have to tackle more mundane tasks. Say, like the genesis and
evolution of the universe. :-)
I don't think they would be safe to let loose on particle accelerators
of humungous power. :-)
Oz
writes
> Baez:
>> For instance, the "set of cattle uncle Bob will own in 2025"
>>refers to things which don't yet exist, but it's perfectly reasonable
>>to talk about the collection anyway. It is just in the future. The
>>same holds for parts of spacetime in our future. The events have not
>>yet occurred, but in physics we may talk about them anyway.
>
> I fail to see the point of this. You say it does not exist (and I
>agree) yet most physicists say that not only does it exist, it can be
>curved by matter and it can affect the motion of matter. Which is it?
>Either it exists or it doesn't. Make up your mind.
I think you are missing the point, by a mile.
When we line up our piece of artillery we work out the path of the shell
*into the future* to work out where it will land. You could do the same
thing using spacetime, of course. However should you then change your
aim or even decide not to fire it you wouldn't expect the world to end.
There is no difference between doing this calculation using spacetime
and using conventional mathematics. Why do you think there should be?
Your problem has at it's root the absolute determination of the future
by the configuration of the present. This was (I think) the idea of
Lagrange and was much argued about until QM made this patently
inapplicable. Using spacetime as a convenient way of visualising and
calculating physical processes is philosophically no different to using
Newtonian methods. No magic involved.
Keith Stein
>of total idiots?
In article <4ledlt$r...@newsbf02.news.aol.com>, SavainL
Well, believe it or not, I'm beginning to seriously ask myself this
very question. I've seen a few things written on sci.physics *by
physicists* that are not too flattering, to say the least. And I can
quote chapter and verse if I have to. You're right though. I would
never say that
physicists are total idiots.
But then again, it could be idiocy, fear, pride, vanity, or just plain
mule-headedness. I really don't care. We all suffer from one
or another. I'm looking for a few people who can see the absurdity of
spacetime and have a serious discussion about it. If needs be, the
discussion can be carried off line so as not to offend the sensibilities
of some physicists. I say "some" because not all would be offended. I
already know of several physicists who agree with me on spacetime. Or
rather, I should say that I agree with *them* on spacetime. And no,
they are not total idiots. Only partially, just like everyone else.
Best regards,
Louis Savain
keith stein wrote:-
'I do not understand.' It was someone quite else that wrote;
'You do not understand', if you understand me, Louis, but i
hope you don't mind my slight editing of your reply to them,
which i thought was excellent.
in reply to me Louis Savain writes:-
> Time, viewed as a spatial dimension, is indeed 100% nonsense
i agree it is 'nonsense' to view 'time' as a 'spatial dimension'.
> It is unfortunate that physicists and philosophers
>have taken to dimensionalizing time.
>
Well i'm not quite sure what you mean by 'dimensionalizing time',
but in the sense that physicists make time 'measurable' with clocks,
i consider this to be their job, rather than unfortunate.
--
Keith Stein
john baez
>In article <4lf30d$6...@newsbf02.news.aol.com>, SavainL <sav...@aol.com>
>writes
>> Baez:
>>> For instance, the "set of cattle uncle Bob will own in 2025"
>>>refers to things which don't yet exist, but it's perfectly reasonable
>>>to talk about the collection anyway. It is just in the future. The
>>>same holds for parts of spacetime in our future. The events have not
>>>yet occurred, but in physics we may talk about them anyway.
>> I fail to see the point of this. You say it does not exist (and I
>>agree) yet most physicists say that not only does it exist, it can be
>>curved by matter and it can affect the motion of matter. Which is it?
>>Either it exists or it doesn't. Make up your mind.
>
>I think you are missing the point, by a mile.
What's that "Baez" doing up there? I didn't write any of that stuff.
Edward Green
>Why do you want to understand, much less "expain", a false
>theory. BTW, thanks for announcing your admittedly expert opinion
>that "it's false". Good for you!
Pouncing on isolated words leads to polarization of argument and breakdown
in free communciation. It's like tabloid journalism... reporter hurredly
scripples down remark by prominent physicist, runs to call in front page
story: "JOHN BAEZ BELIEVES GR IS FALSE!". (Baez leaves country one step
ahead of agents of the GR conspiracy seeking revenge.)
Oz
writes
>In article <$1GgnoAH...@upthorpe.demon.co.uk> O...@upthorpe.demon.co.uk
>writes:
>>In article <4lf30d$6...@newsbf02.news.aol.com>, SavainL <sav...@aol.com>
>>writes
>
>>> Baez:
>>>>refers to things which don't yet exist, but it's perfectly reasonable
>>>>to talk about the collection anyway. It is just in the future. The
>>>>same holds for parts of spacetime in our future. The events have not
>>>>yet occurred, but in physics we may talk about them anyway.
>
>>> I fail to see the point of this. You say it does not exist (and I
>>>agree) yet most physicists say that not only does it exist, it can be
>>>curved by matter and it can affect the motion of matter. Which is it?
>>>Either it exists or it doesn't. Make up your mind.
>>
>
>What's that "Baez" doing up there? I didn't write any of that stuff.
Oh shit. I cocked it up. I misread the post and thought that was
Savaint's quote of the mighty wizard. I must admit it seemed odd at the
time. It didn't have the mighty one's elan.
Grovelling apologies.
Sackcloth and ashes for the rest of the week.
I will self flagellate daily too.
And prostrate myself towards California every four hours.
And eat Hubanos chillies neat.
Is that enough? Oh high and mighty one? :-{
NB Hic. :-)
Keith Stein
writes
> All this "incompleteness of GR / QT" stuff
>is only a matter of principle. There were QT matters, GR doesn't play
>a role at all and vice versa. It is only in EXTREMELY strange and weird
>places (like the first billionth of second of the big bang - or tiny
>black holes) that both of them play a role. These weird places are
>"at the Planck scale".
>If you're a practical guy, you say: GREAT ! So we actually know
>everything (in principle) except for these weird places we'll never
>study anyhow.
>If you are a philosopher, you say SHIT ! We have a principal
>inconsistency between GR and QT, and no experiment in the coming
>500 years (rough guess :) is going to address these matters, so
>we will not know.
>And if you're a crackpot, you silently solve the problem and you
>tell the world that TIME IS BOILING EGG :-)
Cheers,
Patrick.
Albert Einstein: mass is energy.
Patrick Van Esch: Time is egg (a boiling one)
--
Patrick Van Esch
http://www.iihe.ac.be/hep/pp/vanesch
mail: van...@dice2.desy.de
for PGP public key: finger van...@dice2.desy.de
>
>That is the "practical guy viewpoint". The rest is indeed just a matter
>of taste. I more or less adopt the same philosophy, because it must be
>way frustrating to FINALLY UNIFY GR AND QT, and none of your new
>predictions will be verified in the coming 500 years (if ever). We
>actually have (a few thousand) candidate unifications: that's what
>string theory is all about. But the people who work on that NOW will
>never see it confirmed or rejected. Must be a pretty hard thing to
>swallow I guess....
>
>Of course, when I say this to a string theorist, he quite rightly
>corrects me: How can you know ? Right, it MIGHT be that some very
>accessible effect is predicted only by string theory. But I don't
>think so !
>
>> Obviously I haven't been able to catch the real twist. So I have to ask
>you
>> to try to enlighten me further. Will you? Thanks in advance.
>>
>On the contrary, I think you have a rather good view on it.
>
>cheers,
>Patrick.
>
>PS: I won't post this again, I just mailed it to you. You can post it
>if you want to, but here, both of my newsservers are utterly confused
>(the one in Brussels and the one in DESY).
>
>
>Lorenz Borsche (FRG)
>
>Dubium sapientiae initium. [Descartes]
--
Keith Stein
Just so everone knows which crackpot we are talking about.
SavainL
<sth...@sthbrum.demon.co.uk> writes:
>[...]
> 'I do not understand.' It was someone quite else that wrote;
> 'You do not understand', if you understand me, Louis, but i
> hope you don't mind my slight editing of your reply to them,
> which i thought was excellent.
I get the slight feeling that you're using my posts for your own crusade
against physicists. If you are, please reveal it as such as I have
nothing against physicists in general. My beef is with a few absurd
notions and inconsistencies. Spacetime is but one of them.
>in reply to me Louis Savain writes:-
>> Time, viewed as a spatial dimension, is indeed 100% nonsense
>
>i agree it is 'nonsense' to view 'time' as a 'spatial dimension'.
>
>> It is unfortunate that physicists and philosophers
>>have taken to dimensionalizing time.
>>
>Well i'm not quite sure what you mean by 'dimensionalizing time',
>but in the sense that physicists make time 'measurable' with clocks,
>i consider this to be their job, rather than unfortunate.
You're right of course. Thanks for pointing out the ambiguity in my
wording. In this context, I meant to say "spatializing time". By this I
mean that physicists have taken to giving time an independent existence,
apart from motion and distance. Motion and distance, in my opinion, are
the only things with an independent existence. Time is but a ratio of
distance over motion.
john baez
>Grovelling apologies.
>Sackcloth and ashes for the rest of the week.
>I will self flagellate daily too.
>And prostrate myself towards California every four hours.
>And eat Hubanos chillies neat.
>Is that enough? Oh high and mighty one? :-{
No need for all that. Just calculate the Ricci tensor of the big bang
cosmology, starting from your nice-looking results on the Riemann
tensor? All you need to do is sum over a, below:
R_{bc} = R^a_{bac}
Just think how good you will feel when you can say you've used general
relativity to figure out the equations governing the expansion of the
universe!
Tom Potter
> Time, viewed as a spatial dimension, is indeed 100% nonsense as I've
>pointed out elsewhere. It is unfortunate that physicists and
philosophers >have taken to dimensionalizing time.
You have made a couple of key points in this forum:
1. Is the position of an electron intrinsic or extrinsic?
2. Nothing moves in time-space.
BUT I think that you are off base in saying that time should not be
combined with space and dimensionalized.
It is my observation that the fundamental unit of observation
and of information is the cycle.
Time, space, mass and all other properties can be ( And should be )
defined in terms of a single reference cycle.
time(X) = cycles(reference) / cycles(X)
distance(X) = interaction time(X) * C
mass(A) * G = distance(B)^3 / time^2
Note that all other properties can be defined in terms
of the three developed above. ( Time, distance and mass )
Also, there is no zero, nor infinity, as all "points"
must be referenced to some standard cycle. As I have
also posted, any other point ( Time, space, mass, etc )
can be most effectively referenced using a binary search
about a circle.
All things other than cycles, and cycle ratios
are creations of the mind.
Visit my Web site at: http://pobox.com/~tdp
for detailed articles on each of these subjects.
Tom Potter
Scott Ellsworth
>In article <Ramsay-MT-210...@delphi.bc.edu>,
>Rams...@hermes.bc.edu (Keith Ramsay) writes:
>
>>In article <4lbii0$2...@newsbf02.news.aol.com>, sav...@aol.com
>>(SavainL) wrote:
>>Spacetime is clearly not "obvious nonsense", so I think you must be
>>misunderstanding it in some basic way. Spacetime is the set of all
>>events, past, present and future. Not absurd at all.
>
> Spacetime is indeed what you say it is. And that's precisely what makes
>it absurd. It is an unchanging, motionless set. It forbids uncertainty.
>Realities that demand either 100% uncertainty or 100% determinism are
>equally absurd. It's like having a world where only 'left' is permitted
>and 'right' is forbidden, or vice versa. It's nonsense! If this is not
>obvious to you, what's the point of discussing it?
Please. Do not continue to. You have stated your position clearly
enough that anyone who has followed the thread now knows what you think
about spacetime and physics. You have stated (paraphrased) that if
spacetime is needed for a theory, and that theory makes useful
predictions, you will reject the theory rather than accept spacetime, as,
by assumption, spacetime is not true.
It is clear at this point that you have some internal objection to any
predeterministic theory, and that you have concluded that spacetime is
such. As usually presented, BTW, I agree with the second half of your
statement, though that is not relevant to us - we are not in a
position to see the predetermined paths. Consider, even if all of our
actions are predetermined by paths through spacetime and physical laws,
**we** do not have access to the information needed to determine what
will be.
We may well live in a completely predetermined universe, which appears
random. Or we may not, as some QM results would may indicate. Wheeler's
many worlds approach to QM is deterministic in large scale as well, but
last time I checked, there was no way to distinguish Copenhagen and Many
Worlds.
I agree with you - there is really no point in contiuing this
discussion. You have assumed the lack of existence of a major component
of a theory, as usually presented, and therefore cannot communicate with
the reltavists at all. You have assumed the theory which gives the best
predictive value out of existence. Because it does give better
predictions than any other, it can and will be taught, until a better
model comes along.
Scott
--
_____________________________________________________________________________
Scott Ellsworth q...@netcom.com
My opinions are my own EViews ftp: ftp.netcom.com:/pub/qm/qms
Quantitative Micro Software - 714 856 3368
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