The world view of General Relativity
Tom Potter
--
Tom Potter
http://tdp1001.spaces.live.com/
http://www.tompotter.us/misc.html
http://www.geocities.com/tdp1001/index.html
http://notsocrazyideas.blogspot.com
http://www.flickr.com/photos/tom-potter/
http://tdp1001.wiki.zoho.com
http://groups.msn.com/PotterPhotos
http://www.androcles01.pwp.blueyonder.co.uk/dingleberry.htm
Eric Gisse
> http://www.geogreeting.com/view.html?yqDBUGkCDoCUDswo0UwyxoIUkxnUwsxnC
>
> --
> Tom Potterhttp://tdp1001.spaces.live.com/http://www.tompotter.us/misc.htmlhttp://www.geocities.com/tdp1001/index.htmlhttp://notsocrazyideas.blogspot.comhttp://www.flickr.com/photos/tom-potter/http://tdp1001.wiki.zoho.comhttp://groups.msn.com/PotterPhotoshttp://www.androcles01.pwp.blueyonder.co.uk/dingleberry.htm
Clearly GR wastes time. You've written thousands of words about how it
wastes time.
If it didn't waste so much time you wouldn't be wasting so much time
whining about how GR wastes time.
Sam Wormley
Bluster on, Potter, bluster some more! Froth at the mouth! Whatever!
Y.y.Porat
> Bluster on, Potter, bluster some more! Froth at the mouth! Whatever!
--------------------
the problem is not with the partial achievements of GR
the problem is with relating it to 'curves space time' !!
ie
the physical reason of it
all the rest was jsut
trial and error fitting of experimental data
to formulas
so you might ask
whats wrong with it as long it gives us some
real results ???
i say
it is wrong for further advance of science
i always bring that methaphore : !!
opepel knew how to use fire very prctially
and nicely thousands of years ago !!
**but it was ***only after*** better and more realistic
understanding about what fire is
and how and why its works
that
THE INNER COMBUSTION ENGINE COULD BE INVENTED !!!!
got it
for once and for all ??
space is nothing and cannot have any properties
except hosting mass
gravity is a property of **mass**
not of space !!!
ATB
Y.Porat
------------------------
Eric Gisse
> On May 4, 4:20 am, Sam Wormley <sworml...@mchsi.com> wrote:
>
> > Bluster on, Potter, bluster some more! Froth at the mouth! Whatever!
>
> --------------------
> the problem is not with the partial achievements of GR
> the problem is with relating it to 'curves space time' !!
> ie
> the physical reason of it
So basically, as usual, you have no fucking reason to dislike GR
except that it bumps up against the inflexible notions of a retired
structural engineer with no training in the physical sciences.
> all the rest was jsut
> trial and error fitting of experimental data
> to formulas
That isn't how it works, homeslice.
[snip rest]
Y.y.Porat
--------------------
imbecile psychopath parrot
Y.P
-------------------
Ahmed Ouahi, Architect
Whatsoever, the problem, is more deeper as a simply along the surface, in
the same time, as to which, it could be somehow an infinite perspectives as
a possibilities, that the problem would be resolved along a topological
space moving, all along...
However, a simply because, along any conventional correction of a general
relativity, seems certainly for an official specific goal, or a simply a
military matter after their having their own mass-media which allows them, a
definitely their own behaviours for the others, all along...
Therefore, as a definitely along that matter, it is, that the general
relativity along its correction, has had to reduce the gravity strength
along a spacetime, as along any space behaviours as out of any time, for the
simple reason, that a definitely, the motion could not and ever be
controled, a definitely as a matter a fact...
--
Ahmed Ouahi, Architect
Best Regards!
"Y.y.Porat" <y.y....@gmail.com> kirjoitti
viestiss�:0305eb17-a137-49ae...@q2g2000vbr.googlegroups.com...
Sam Wormley
> Whatsoever, the problem, is more deeper as a simply along the surface, in
> the same time, as to which, it could be somehow an infinite perspectives as
> a possibilities, that the problem would be resolved along a topological
> space moving, all along...
>
> However, a simply because, along any conventional correction of a general
> relativity, seems certainly for an official specific goal, or a simply a
> military matter after their having their own mass-media which allows them, a
> definitely their own behaviours for the others, all along...
>
> Therefore, as a definitely along that matter, it is, that the general
> relativity along its correction, has had to reduce the gravity strength
> along a spacetime, as along any space behaviours as out of any time, for the
> simple reason, that a definitely, the motion could not and ever be
> controled, a definitely as a matter a fact...
>
ILLUCID
Ahmed Ouahi, Architect
Fuck you!
--
Ahmed Ouahi, Architect
Best Regards!
"Sam Wormley" <swor...@mchsi.com> kirjoitti
viestiss�:1yILl.88132$DP1.58184@attbi_s22...
hanson
>
"Ahmed Ouahi, Architect" <ahmed...@welho.com>
cranked himself over Sam, and with his best regards he wrote:
>
"Sam Wormley" <swor...@mchsi.com> kirjoitti
viestiss�:1yILl.88132$DP1.58184@attbi_s22...
>>
Ahmed Ouahi, Architect wrote:
Whatsoever, the problem, is more deeper as a simply along the
surface, in the same time, as to which, it could be somehow an
infinite perspectives as a possibilities, that the problem would
be resolved along a topological space moving, all along...
However, a simply because, along any conventional correction
of a general relativity, seems certainly for an official specific goal,
or a simply a military matter after their having their own mass-media
which allows them, a definitely their own behaviours for the others,
all along... Therefore, as a definitely along that matter, it is, that the
general relativity along its correction, has had to reduce the gravity
strength along a spacetime, as along any space behaviours as out
of any time, for the simple reason, that a definitely, the motion could
not and ever be controled, a definitely as a matter a fact...
>>>
ILLUCID
>
"Ahmed Ouahi, Architect" wrote:
Fuck you! -- Best Regards!
>
hanson wrote:
Achmed, it appears that Sam did not like your architecture.
However, the fact that you wish to fuck Sam with your best
regards, may cause Sam to ameliorate and express his
judgenemt less loudly by NOT using Capital letters...
Thanks for the laughs, guys... ahahaha...ahahahanson
>
Ahmed Ouahi, Architect
Maybe, that would be an absolute reason, that first of all, he could fuck
hismelf, before of thinking a being a teacher, as already it seems, also,
that he is one the best as an empty from upstairs, definitely as a matter a
fact!
--
Ahmed Ouahi, Architect
Best Regards!
"hanson" <han...@quick.net> kirjoitti
viestiss�:yjKLl.2471$fy....@nwrddc01.gnilink.net...
> ------- AHAHAHAHA.... Good one!... AHAHAHAHAHA --------
>>
> "Ahmed Ouahi, Architect" <ahmed...@welho.com>
> cranked himself over Sam, and with his best regards he wrote:
>>
> "Sam Wormley" <swor...@mchsi.com> kirjoitti
> viestiss�:1yILl.88132$DP1.58184@attbi_s22...
Eric Gisse
I'm sorry, did I somehow manage to once again offend the terminally
uneducated?
Sam Wormley
> Maybe, that would be an absolute reason, that first of all, he could fuck
> hismelf, before of thinking a being a teacher, as already it seems, also,
> that he is one the best as an empty from upstairs, definitely as a matter a
> fact!
>
His milf?
Tom Roberts
> the problem is not with the partial achievements of GR
> the problem is with relating it to 'curves space time' !!
> ie
> the physical reason of it
> all the rest was jsut
> trial and error fitting of experimental data
> to formulas
You REALLY do not have a clue. In GR there are only three parameters
that could be used for "error fitting of experimental data". They are:
c the local universal speed of the Lorentz transform
(also the local speed of light in vacuum)
G the gravitational constant
L the cosmological constant
For most experiments that are considered to be tests of GR, L is
unmeasurable except that it must be very small. This is consistent with
the cosmological measurements (there is too much uncertainty in them and
in cosmological models to consider them tests of GR).
So TWO experiments are sufficient to determine the parameters of
interest. After that, there is NO WAY AT ALL to do "error fitting of
experimental data", simply because the entire theory is COMPLETELY
DETERMINED.
As I have said before, you need to STUDY modern physics and get an
education.
Tom Roberts
funkenstein
Well I think empirical physics is necessary to build an internal
combustion engine. I'd happily defend empiricism but Tom is right: a
less empirical theory than GR is hard to find, so I'll save that rant
for another thread.
Juan R.
(...)
> In GR there are only three parameters
> that could be used for "error fitting of experimental data". They are:
> c the local universal speed of the Lorentz transform
> (also the local speed of light in vacuum)
> G the gravitational constant
> L the cosmological constant
Those are not parameters in GR but universal constants. The symbol for
cosmological constant is Lambda.
In a PPN formalism the parameters for GR are alpha, beta, gamma...
--
http://www.canonicalscience.org/
Usenet Guidelines:
http://www.canonicalscience.org/en/miscellaneouszone/guidelines.html
hanson
>
"Sam Wormley" <swor...@mchsi.com> suggested to Ahmed & wrote:
> "Ahmed Ouahi, Architect" <ahmed...@welho.com>
> cranked himself over Sam, and with his best regards he wrote:
>>
Ahmed Ouahi, Architect wrote:
Whatsoever, the problem, is more deeper as a simply along the
surface, in the same time, as to which, it could be somehow an
infinite perspectives as a possibilities, that the problem would
be resolved along a topological space moving, all along...
However, a simply because, along any conventional correction
of a general relativity, seems certainly for an official specific goal,
or a simply a military matter after their having their own mass-media
which allows them, a definitely their own behaviours for the others,
all along... Therefore, as a definitely along that matter, it is, that the
general relativity along its correction, has had to reduce the gravity
strength along a spacetime, as along any space behaviours as out
of any time, for the simple reason, that a definitely, the motion could
not and ever be controled, a definitely as a matter a fact...
>>>
"Sam Wormley", Teacher wrote:
ILLUCID
>
"Ahmed Ouahi, Architect" wrote:
Fuck you! -- Best Regards!
>
hanson wrote:
Achmed, it appears that Sam did not like your architecture.
However, the fact that you wish to fuck Sam with your best
regards, may cause Sam to ameliorate and express his
judgenemt less loudly by NOT using Capital letters...
Thanks for the laughs, guys... ahahaha...ahahahanson
>
Maybe, that would be an absolute reason, that first of all, he
as already it seems, also, that he is one the best as an empty
>
"Sam Wormley", Teacher wrote:
>
hanson wrote:
Ahmed, do you realize what Sam, the Teacher, just insinuated
you do? It is not clear whether Sam has the best regards for you.
See here what "milf" stands for: http://tinyurl.com/7rtvf
>
So Ahmed, you should not let that Teacher's insinuation go
unanswered, for if you investigate that Teacher & rearrange
the architecture of the letters in "Sam Wormley" you will find
that it also stands for a "Sly Raw Memo" by a "Measly Worm"
Carry on, and thanks for the laughs, guys.... ahahahahanson
Ahmed Ouahi, Architect
the earth has had always succeed, as always would be, no metter, any
behaviours all around, whether an extra oxygen matter has had been produced
one way or an other, all along...
Therefore, certainly, a bacteria would not build any cities or would be
having any attractive social life, but they would always be here whether the
sun would a definitely be, none does knows, neither, but it is the way would
be, as that is a fact, a definitely as a matter a fact...
--
Ahmed Ouahi, Architect
Best Regards!
"hanson" <han...@quick.net> kirjoitti
viestiss�:Ao0Ml.4612$b11....@nwrddc02.gnilink.net...
Tom Roberts
> Tom Roberts wrote on Tue, 05 May 2009 09:02:18 -0700:
>> In GR there are only three parameters
>> that could be used for "error fitting of experimental data". They are:
>> c the local universal speed of the Lorentz transform
>> (also the local speed of light in vacuum)
>> G the gravitational constant
>> L the cosmological constant
>
> Those are not parameters in GR but universal constants.
Call them what you like, they are the only possible values that can be
used to fit GR to experiments. Their "universality" is simply due to the
fact that in GR they are constants -- "universal" just means they don't
depend on location or coordinates (as constants must); this is of course
model dependent (GR is the model here).
> In a PPN formalism the parameters for GR are alpha, beta, gamma...
Those are NOT "parameters for GR", they are parameters of the
Parameterized Post-Newtonian formalism. GR is just one specific point in
its parameter space. That is, these parameters CANNOT be varied and
still yield GR, they must have those specific values. The PPN formalism
is a "meta-theory" useful as a test theory of GR.
Tom Roberts
Sam Wormley
>
> Therefore, certainly, a bacteria would not build any cities or would be
> having any attractive social life, but they would always be here whether the
> sun would a definitely be, none does knows, neither, but it is the way would
> be, as that is a fact, a definitely as a matter a fact...
>
That's a biased opinion, of which you are entitled.
Beauty is a pretty subjective term. Many find general relativity to be
quite beautiful.
Ref: http://en.wikipedia.org/wiki/General_relativity
"General relativity or the general theory of relativity is the geometric
theory of gravitation published by Albert Einstein in 1916. It is the
current description of gravity in modern physics. It unifies special
relativity and Newton's law of universal gravitation, and describes
gravity as a property of the geometry of space and time, or spacetime.
In particular, the curvature of spacetime is directly related to the
four-momentum (mass-energy and linear momentum) of whatever matter and
radiation are present. The relation is specified by the Einstein field
equations, a system of partial differential equations".
Ahmed Ouahi, Architect
" The increasing distance of the physical world picture from the world of
the senses means nothing but a progressive approach to the real world. "
-- Max Planck
--
Ahmed Ouahi, Architect
Best Regards!
"Sam Wormley" <swor...@mchsi.com> kirjoitti
viestiss�:gM1Ml.685572$yE1.474485@attbi_s21...
Sam Wormley
> " The increasing distance of the physical world picture from the world of
> the senses means nothing but a progressive approach to the real world. "
>
> -- Max Planck
>
>
What do you say Ahmed?
Ahmed Ouahi, Architect
Certainly, along, the relativity, that is the most nearest approach, to any
behaviours of nature, as it has had a definitely disturbed any political
behaviours, all along!
--
Ahmed Ouahi, Architect
Best Regards!
"Sam Wormley" <swor...@mchsi.com> kirjoitti
viestiss�:6a2Ml.685610$yE1.317413@attbi_s21...
Juan R.
> Juan R. González-Álvarez wrote:
>> Tom Roberts wrote on Tue, 05 May 2009 09:02:18 -0700:
>>> In GR there are only three parameters that could be used for "error
>>> fitting of experimental data". They are:
>>> c the local universal speed of the Lorentz transform
>>> (also the local speed of light in vacuum)
>>> G the gravitational constant
>>> L the cosmological constant
>>
>> Those are not parameters in GR but universal constants.
>
> Call them what you like,
I call them by its name
http://online.cctt.org/physicslab/content/aaptdrillforms/constants.asp
http://en.wikipedia.org/wiki/
Physical_constant#Table_of_universal_constants
>> In a PPN formalism the parameters for GR are alpha, beta, gamma...
>
> Those are NOT "parameters for GR"
Either you do not understand I wrote or you do not understand PPN. In
this formalism, "general relativity has PPN parameters..." [1]
"The parameters γ and β are [...] the only non-zero parameters in GR" [2]
Maybe you believe that all above quotes mean that the values for alpha,
beta, gamma... can be changed for GR, but is not true.
[1]
http://en.wikipedia.org/wiki/Parameterized_post-Newtonian_formalism
[2]
http://relativity.livingreviews.org/Articles/lrr-2006-3/
articlesu5.html#x11-190003.2
Sam Wormley
> Certainly, along, the relativity, that is the most nearest approach, to any
> behaviours of nature, as it has had a definitely disturbed any political
> behaviours, all along!
>
I'm glad you agree!
hanson
What do you say Ahmed?
>
... ahahahaha...Sam, it looks like the Architect is teaching the
Teacher that:
>
=P= "Experiments are the only means of knowledge at
=P= our disposal. The rest is poetry and imagination."
=P= Max Planck ~1894.
>
That's the same Max Planck who was Einstein's mentor and
his intellectual superior. .. ahahaha... AHAHAHAHAHA....
But Albert, the "nitwit, a plagiarist, & liar (acc to koobee.wublee)
did not heed his Boss' advice and he went instead onto the band-
wagon of the Zios who promoted him & his "Juden Physik" which
bred vast hordes of Einstein Dingleberries, all being devout and
fanatical worshippers of Einstein's phantasms that emanated from
his sphincter. As can be seen in these NG's and elsewhere on the
web, all Einstein Dingleberries are mentally damaged goods that
never knew that Albert and his Zios took them for a ride. "oye weh!"
"Trust Me!"..."Go Figure"... ahahahaha,,,
>
Maybe these are the "best regards" that the Architect is giving you.
Thanks for the laughs, guys... AHAHAHAHA... ahahahahahanson
RustyJames
a dialectric value and resistance sounds like a property to me, also
negative pressure value
carlip...@physics.ucdavis.edu
> Tom Roberts wrote on Tue, 05 May 2009 13:31:17 -0700:
> > Juan R. González-Álvarez wrote:
[...]
> >> In a PPN formalism the parameters for GR are alpha, beta, gamma...
> > Those are NOT "parameters for GR"
> Either you do not understand I wrote or you do not understand PPN. In
> this formalism, "general relativity has PPN parameters..." [1]
> "The parameters ?? and ?? are [...] the only non-zero parameters in GR" [2]
The PPN "parametrized post-Newtonian" approximation is a general
framework for describing theories of gravity that are approximately
Newtonian for weak fields. The PPN parameters are coordinates on a
"space of theories." General relativity is a particular "point" in this
space of theories -- it has definite values of the PPN parameters, which
can be calculated from the field equations.
Tom is absolutely correct in saying that the PPN parameters are not
adjustable parameters in GR. What he said (had you not taken one
sentence out of context) was
Those are NOT "parameters for GR", they are parameters of the
Parameterized Post-Newtonian formalism. GR is just one specific point in
its parameter space. That is, these parameters CANNOT be varied and
still yield GR, they must have those specific values. The PPN formalism
is a "meta-theory" useful as a test theory of GR.
There is no adjustable parameter *in GR* that can be changed to change
the values of the PPN parameters. Once you have specified that you are
talking about GR and not some other theory, the values of the PPN
parameters are fixed. In particular, as Tom said, you cannot do "error
fitting of experimental data" within GR -- apart from measured coupling
constants, there are no adjustable parameters that can be adjusted to
fit data.
Steve Carlip
Tom Roberts
> Tom Roberts wrote on Tue, 05 May 2009 13:31:17 -0700:
>> Juan R. González-Álvarez wrote:
>>> In a PPN formalism the parameters for GR are alpha, beta, gamma...
>> Those are NOT "parameters for GR"
> "The parameters γ and β are [...] the only non-zero parameters in GR" [2]
> Maybe you believe that all above quotes mean that the values for alpha,
> beta, gamma... can be changed for GR, but is not true.
Right. If you had better reading skills in English you would know that
you and I are saying the same thing using different words. Your initial
post implied that the values of these PPN parameters could vary in GR
(without stating it explicitly); I clarified that, and you repeated my
clarification as if you were disagreeing with what I said.
Tom Roberts
hanson
> Juan R. González-à lvarez wrote:
>> Tom Roberts wrote on Tue, 05 May 2009 13:31:17 -0700:
>>>> In a PPN formalism the parameters for GR are alpha, beta, gamma...
>>> Those are NOT "parameters for GR"
>> In this formalism, "general relativity has PPN parameters..." [1]
>> [2]
>> Maybe you believe that all above quotes mean that the values for alpha,
>> beta, gamma... can be changed for GR, but is not true.
>
>
Right. If you, Juan R., had better reading skills in English you
would know that you and I are saying the same thing using different
words. Your initial post implied that the values of these PPN
parameters could vary in GR (without stating it explicitly);
I clarified that, and you repeated my clarification as if you were
>
hanson wrote:
Wrong. This issue has nothing to do with any language skills.
It has to do everything with the essence of Einstein's crap.
All SR/GR does is to create Einstein Dingleberries who
argue with each other ... like you guys just did... ahaha...
>
Don't feel bad though. It happens daily. In every discussion
of/about Einstein's crap: To argue over the same shit 100
years after the advent of SR/GR should tell you that you
Einstein Dingleberries are not any different than rabbis,
priests or mullahs who like you hang into their ancient
scriptures and interpret them according to their own whim.
>
Even the enviro turds are a smarter then relativists.
The Greens at least say: "the debate is over" & do demand
action... But you Relas have no action to show nor to goto...
Thanks for the laughs, though... ahahahahanson
Juan R.
> In sci.physics Juan R. González-Álvarez
> <juanR...@canonicalscience.com> wrote:
>> Tom Roberts wrote on Tue, 05 May 2009 13:31:17 -0700:
>
>> > Juan R. González-Álvarez wrote:
>
> [...]
>> >> In a PPN formalism the parameters for GR are alpha, beta, gamma...
>
>> > Those are NOT "parameters for GR"
>
>> Either you do not understand I wrote or you do not understand PPN. In
>> this formalism, "general relativity has PPN parameters..." [1]
>
>> "The parameters ?? and ?? are [...] the only non-zero parameters in GR"
>> [2]
(...)
> The PPN parameters are coordinates on a
> "space of theories." General relativity is a particular "point" in this
> space of theories -- it has definite values of the PPN parameters,
(...)
> There is no adjustable parameter *in GR* that can be changed to change
> the values of the PPN parameters. Once you have specified that you are
> talking about GR and not some other theory, the values of the PPN
> parameters are fixed.
You would not need to type this if you had read the part of my message
saying
"Maybe you believe that all above quotes mean that the values for alpha,
beta, gamma... can be changed for GR, but is not true."
Juan R.
> Juan R. González-Álvarez wrote:
>> Tom Roberts wrote on Tue, 05 May 2009 13:31:17 -0700:
>>> Juan R. González-Álvarez wrote:
>>>> In a PPN formalism the parameters for GR are alpha, beta, gamma...
>>> Those are NOT "parameters for GR"
>> In this formalism, "general relativity has PPN parameters..." [1] "The
>> parameters γ and β are [...] the only non-zero parameters in GR" [2]
>> Maybe you believe that all above quotes mean that the values for alpha,
>> beta, gamma... can be changed for GR, but is not true.
>
> Right. If you had better reading skills in English you would know that
> you and I are saying the same thing using different words. Your initial
> post implied that the values of these PPN parameters could vary in GR
> (without stating it explicitly); I clarified that, and you repeated my
> clarification as if you were disagreeing with what I said.
If your "skills in English" are the basis for your above claims that
universal constant are "parameters in GR" or for your belied that quotes
as "the parameters for GR are alpha, beta, gamma...", "general relativity
has PPN parameters...", "The parameters γ and β are [...] the only non-
zero parameters in GR" mean something different they mean I cannot really
help you.
Juan R.
universal constants are "parameters in GR" or for your beliefs that quotes
as "the parameters for GR are alpha, beta, gamma...", "general
relativity has PPN parameters...", "The parameters γ and β are [...] the
only non- zero parameters in GR" mean something different they really
carlip...@physics.ucdavis.edu
> carlip-nospam wrote on Wed, 06 May 2009 15:36:32 +0000:
[...]
> > The PPN parameters are coordinates on a
> > "space of theories." General relativity is a particular "point" in this
> > space of theories -- it has definite values of the PPN parameters,
[...]
> > There is no adjustable parameter *in GR* that can be changed to change
> > the values of the PPN parameters. Once you have specified that you are
> > talking about GR and not some other theory, the values of the PPN
> > parameters are fixed.
> You would not need to type this if you had read the part of my message
> saying
> "Maybe you believe that all above quotes mean that the values for alpha,
> beta, gamma... can be changed for GR, but is not true."
You're right -- I missed this.
I'm a bit confused, though. Tom Roberts was responding to a post that
claimed that general relativity was "trial and error fitting of experimental
data to formulas." His basic point was that GR has no adjustable parameters
to "fit" to the data, apart from the coupling constants -- it either agreed with
the data or didn't. I now take it that you agree with this?
Steve Carlip
Juan R.
> In sci.physics Juan R. Gonz�lez-�lvarez
I am not really sure what you are asking. Tom also wrote:
In GR there are only three parameters
that could be used for "error fitting of experimental data". They are:
c the local universal speed of the Lorentz transform
(also the local speed of light in vacuum)
G the gravitational constant
L the cosmological constant
I do not know if you are asking me if I agree with Tom about this. (No)
If you are asking me if I agree with original poster claim. No
Or if you are asking me if I agree that *any* experimental/observational
confrontation of GR with data is parameter free. Again the response is No.
Juan R.
Of course, I mean that several models used in GR are based in parameters.
Two typical examples are cosmological models and galactic models. Yes GR,
as theory, has no adjustable parameters but when confronting galactic
rotation curves to GR, people use models with two, three, or more
parameters, which are fitted to data.
Due to use of unknown parameters in those models GR is not predictive.
E.g. it is not possible to predict rotation profiles for hundred of
galaxies, and experimentalists merely do an exercise in data fitting.
For cosmology it was not possible to predict the second peak in WMAP...
Androcles
"Juan R. Gonz�lez-�lvarez" <juanR...@canonicalscience.com> wrote in
message news:pan.2009.05...@canonicalscience.com...
> Of course, I mean that several models used in GR are based in parameters.
> Two typical examples are cosmological models and galactic models. Yes GR,
> as theory, has no adjustable parameters but when confronting galactic
> rotation curves to GR, people use models with two, three, or more
> parameters, which are fitted to data.
http://www.androcles01.pwp.blueyonder.co.uk/Shapiro/Crapiro.htm
If spacetime is curved, is the curvature convex or concave?
Tom Roberts
> Of course, I mean that several models used in GR are based in parameters.
> Two typical examples are cosmological models and galactic models. Yes GR,
> as theory, has no adjustable parameters but when confronting galactic
> rotation curves to GR, people use models with two, three, or more
> parameters, which are fitted to data.
Sure. But those parameters are NOT parameters of GR. They are, rather,
parameters that specify some as-yet-unknown matter and/or interactions
or "stuff" out there.
> Due to use of unknown parameters in those models GR is not predictive.
It is not GR that is "not predictive", it is those models that are not
completely predictive. But, of course, using parameterized distributions
and models to fit our lack of knowledge is a common and reasonable thing
to do. And generally there are fewer parameters in the model than there
are data points, so obtaining good fits _IS_ "predictive", at least partly.
When a fit with (say) 3 free parameters gives a good chi-sq
for a hundred data points, the model used probably does
represent the data reasonably well.
> E.g. it is not possible to predict rotation profiles for hundred of
> galaxies, and experimentalists merely do an exercise in data fitting.
> For cosmology it was not possible to predict the second peak in WMAP...
Yes. But, of course, these are not shortcomings of GR, they are
shortcomings of our current knowledge about the composition of distant
galaxies in the world we inhabit.
Tom Roberts
Juan R.
> Juan R. Gonz�lez-�lvarez wrote:
>> Of course, I mean that several models used in GR are based in
>> parameters. Two typical examples are cosmological models and galactic
>> models. Yes GR, as theory, has no adjustable parameters but when
>> confronting galactic rotation curves to GR, people use models with two,
>> three, or more parameters, which are fitted to data.
>
> Sure. But those parameters are NOT parameters of GR. They are, rather,
> parameters that specify some as-yet-unknown matter and/or interactions
> or "stuff" out there.
I just do not understand why you repeat I am saying "Yes GR, as theory,
has no adjustable parameters but [...] people use models with two, three,
or more parameters [...]"
>> Due to use of unknown parameters in those models GR is not predictive.
>
> It is not GR that is "not predictive", it is those models that are not
> completely predictive.
Both the specific model and the underlying general theory are not
predictive. However other theories showed to be completely predictive for
the same systems under study.
> But, of course, using parameterized distributions
> and models to fit our lack of knowledge is a common and reasonable thing
> to do.
When there is nothing better at hand? Sure, but when I can use a theory
to predict result before observation, I will be not fiting data /a
posteriori/ using GR.
(...)
>> E.g. it is not possible to predict rotation profiles for hundred of
>> galaxies, and experimentalists merely do an exercise in data fitting.
>> For cosmology it was not possible to predict the second peak in WMAP...
>
> Yes. But, of course, these are not shortcomings of GR, they are
> shortcomings of our current knowledge about the composition of distant
> galaxies in the world we inhabit.
If you assume the hypotesis that GR is correct at those scales then yes,
are not shortcomings for GR but would be needed to build a new theory of
matter for those regions. Now if we assume that current theory of matter
works, then the problem is in GR.
Do not try to convince me that the alternative theory whose predictions
have been all verified is wrong but the theory (GR) giving no prediction,
or even some few false predictions, is the right one :-)
Regards
Tom Roberts
> Tom Roberts wrote on Sat, 09 May 2009 10:24:09 -0500:
>> Juan R. Gonz�lez-�lvarez wrote:
>>> Of course, I mean that several models used in GR are based in
>>> parameters. Two typical examples are cosmological models and galactic
>>> models. Yes GR, as theory, has no adjustable parameters but when
>>> confronting galactic rotation curves to GR, people use models with two,
>>> three, or more parameters, which are fitted to data.
>> Sure. But those parameters are NOT parameters of GR. They are, rather,
>> parameters that specify some as-yet-unknown matter and/or interactions
>> or "stuff" out there.
>
> I just do not understand why you repeat I am saying "Yes GR, as theory,
> has no adjustable parameters but [...] people use models with two, three,
> or more parameters [...]"
Because you manage to phrase your agreement so antagonistically it looks
like disagreement.
>> It is not GR that is "not predictive", it is those models that are not
>> completely predictive.
>
> Both the specific model and the underlying general theory are not
> predictive.
Not true. GR predicts many experimental results, such as:
A) precession of perihelia (Mercury - Mars, ...)
B) gravitational time dilation
C) Shapiro time delay
D) bending of light by the sun
E) ... lots more terrestrial and solar system measurements
The key thing is: do we know the physical conditions, or not? On earth
and in the solar system we do, and GR is quite "predictive", and its
predictions are confirmed by measurements and experiments.
In distant parts of the galaxy, and outside our galaxy, we do not have
complete knowledge of physical conditions, and NO theory can be fully
"predictive".
> Do not try to convince me that the alternative theory whose predictions
> have been all verified is wrong but the theory (GR) giving no prediction,
> or even some few false predictions, is the right one :-)
Sure. But do not claim that unpublished "theories" are better than
well-accepted theories like GR. Ditto for published theories that have
not achieved general acceptance in the community.
Tom Roberts
Juan R.
> Juan R. Gonz�lez-�lvarez wrote:
>> Tom Roberts wrote on Sat, 09 May 2009 10:24:09 -0500:
>>> Juan R. Gonz�lez-�lvarez wrote:
>>>> Of course, I mean that several models used in GR are based in
>>>> parameters. Two typical examples are cosmological models and galactic
>>>> models. Yes GR, as theory, has no adjustable parameters but when
>>>> confronting galactic rotation curves to GR, people use models with
>>>> two, three, or more parameters, which are fitted to data.
>>> Sure. But those parameters are NOT parameters of GR. They are, rather,
>>> parameters that specify some as-yet-unknown matter and/or interactions
>>> or "stuff" out there.
>>
>> I just do not understand why you repeat I am saying "Yes GR, as theory,
>> has no adjustable parameters but [...] people use models with two,
>> three, or more parameters [...]"
>
> Because you manage to phrase your agreement so antagonistically it looks
> like disagreement.
Then again your poor grasp of English managed you to not understand
phrases like "Yes GR, as theory has no adjustable parameters".
>>> It is not GR that is "not predictive", it is those models that are not
>>> completely predictive.
>>
>> Both the specific model and the underlying general theory are not
>> predictive.
>
> Not true. GR predicts many experimental results, such as:
> A) precession of perihelia (Mercury - Mars, ...) B) gravitational time
> dilation
> C) Shapiro time delay
> D) bending of light by the sun
> E) ... lots more terrestrial and solar system measurements
What fascinating misreading!!!
Of course ABCDE are predictions of GR. However, if you had really read
the messsages you would first notice that I wrote
Both the specific model and the underlying general theory are not
predictive. However other theories showed to be completely predictive
for the same systems under study.
after writting
"Two typical examples are cosmological models and galactic models."
For the specific case of galactic rotation curves I wrote in a previous
message GR is *not* predictive, whereas other theories just *are*.
> In distant parts of the galaxy, and outside our galaxy, we do not have
> complete knowledge of physical conditions, and NO theory can be fully
> "predictive".
Plain wrong.
> Sure. But do not claim that unpublished "theories" are better than
> well-accepted theories like GR.
Liar, the theories are published in mainstream journals of physics and
astronomy. Just abandon your cavern and take a look to modern physics
literature.
Regards.