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Science Forum Index » Physics - Relativity Forum » The speed of gravity revisited
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| Tom Roberts |
 Posted: Sat Mar 08, 2008 4:26 pm |
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Juan R. González-Ãlvarez wrote:
Quote: Tom Roberts wrote on Sat, 08 Mar 2008 02:11:31 +0000:
Hmmm. Crizing a non-relativistic theory because fails on relativistic
regimes is very old relativistic tactic but is clearly unfair.
Criticizing a non-relativistic theory for disagreeing with experiments
is not "unfair" at all. This is supposed to be science, and YOU are the
one pushing NG.
Quote: And the usual meaning
of "relativistic effects" does not apply to any of the measurements I
mentioned.
Sure perihelions for Mercury, the Shapiro time delay, bending of EM
radiation by the sun, and GPS operation contain relativistic effects, if
one takes the general meaning not just a kinematic meaning.
Hmm. The usual meaning of "relativistic effects" is that they are
important only for speeds approaching c (SR) or very strong fields (GR).
None of the experiments I mentioned have either.
You seem to mean "relativistic effects" when the non-relativistic theory
fails. That's silly, and useless -- for good enough measurement
resolution the non-relativistic theory is completely useless. Several of
the experiments I mentioned have extraordinarily good resolutions, and
_that_ is why they are important.
Quote: As explained before NG does not exactly fail to explain relativistic
effects. That is wrong claim. NG does not apply to relativistic phenomena
because is a non-relativistic theory.
There is no "relativistic phenomena" involved in ANY of the experiments
I mentioned, unless one uses your silly meaning.
Quote: Nobody would imagine one can apply NG *outside* its range of validity
waiting adequate answer, unless that person does not understand SCIENCE.
Ok. I'm not the one pushing NG, you are. Note its "range of validity"
depends on one's measurement accuracy, and for good enough accuracy its
"range" is essentially empty. Certainly such accuracy is common today (a
$200 GPS receiver), and will be even more common in the future as
measurement techniques improve.
Quote: [my list of experiments, totally corrupted and now unreadable]
This table has been clearly done to confound readers.
The "confounding" is all yours.
Quote: Computes total values for entries making *sense* and try next ratio
NG value
_________________________________________
NG value + relativistic correction
That is a very silly way to do this. And your denominator is outrageous
-- it should at least be "GR value".
Note, however, the CORRECT way to do this is to compare the theories via
these two ratios:
|NGvalue - Experiment| / sigma_experiment
|GRvalue - Experiment| / sigma_experiment
[sigma_experiment is the experimental resolution.]
When one does that, one finds that for EVERY ONE of the experiments I
mentioned the NGvalue is so different from the experimental value that
NG is soundly refuted; the GR value is quite reasonable for all of them.
Quote: "Yours is a statement of profound ignorance in all of its parts."
--- Uncle Al to Tom Roberts. Feb 2008
I merely remark that neither Uncle Al nor you have ever responded to my
followup -- in the physics community it is quite common to consider
one's understanding of a subject to be measured by the ability to
explain it to a graduate student or postdoc not expert in the field. You
both fail that criterion, and instead rely on "dense spews of jargon
indistinguishable from nonsense" [Tom Roberts to Uncle Al, in the thread
you quoted].
Quote: But NG can be quantized without the further problems of GR!
Whyever would that matter? -- who cares about a demonstrably incorrect
and soundly refuted theory like NG?
That's like claiming 2+2=5 can be generalized without the
"problems" of number theory.
Tom Roberts |
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| Guest |
| Posted: Sat Mar 08, 2008 6:07 pm |
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On Mar 7, 2:56 pm, Eric Gisse <jowr...@gmail.com> wrote:
Quote: On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
[...]
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
Like all words, each of these will represent a different concept for
all listeners. I'd like to take your advice and learn just what these
concepts represent.
In no way do they resemble one another?
How about the following ways:
1) they can both be used to describe something that in some way "fills
all space"
2) they both can be used as what is the medium for electromagnetic
radiation
3) they can both be described by spatial and temporal coordinates
4) when "empty", these terms can represent in some way a vacuum
5) we can speak of "curvature" of both things
6) they are both physics concepts emerging from our understanding of
electromagnetism
7) they both frequent this newsgroup
 neither one can be directly physically "measured" (?)
Of course it wouldn't be fair to not list some obvious differences
1) spacetime a new term, ether an older word from when people didn't
know as much
2) spacetime can refer to descriptions of coordinates and
computational methodology (3+1 dimensions, transformations), aether
not so much
3) ether is in common parlance used as a description for an
information manifold, e.g. the EM spectrum or sending emails out to
the ether, spacetime not so much
Cheers - |
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| Juan R." González-Álvarez |
| Posted: Sun Mar 09, 2008 6:13 am |
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Tom Roberts wrote on Sat, 08 Mar 2008 20:26:21 +0000:
Quote: Juan R. González-Ãlvarez wrote:
Tom Roberts wrote on Sat, 08 Mar 2008 02:11:31 +0000: Hmmm. Crizing a
non-relativistic theory because fails on relativistic regimes is very
old relativistic tactic but is clearly unfair.
Criticizing a non-relativistic theory for disagreeing with experiments
is not "unfair" at all.
English may be not your natural language.
I said
Criticizing a non-relativistic theory for disagreeing with relativistic
experiments is "unfair" at all.
Quote: Sure perihelions for Mercury, the Shapiro time delay, bending of EM
radiation by the sun, and GPS operation contain relativistic effects,
if one takes the general meaning not just a kinematic meaning.
Hmm. The usual meaning of "relativistic effects" is that they are
important only for speeds approaching c (SR) or very strong fields (GR).
None of the experiments I mentioned have either.
Completely wrong. E.g. anomaly Mercury perihelion is explained by two
relativistic corrections.
But since you only look to "how" instead "why" you lack understanding.
Quote: Nobody would imagine one can apply NG *outside* its range of validity
waiting adequate answer, unless that person does not understand
SCIENCE.
Ok. I'm not the one pushing NG, you are.
One of your usual FALSE accusations tactics. Read i exactly said.
Quote: [my list of experiments, totally corrupted and unreadable]
When one does that, one finds that for EVERY ONE of the experiments I
mentioned the NGvalue is so different from the experimental value that
NG is soundly refuted; the GR value is quite reasonable for all of them.
No SERIOUS scientist would apply a theory outside its range of
applicability waiting meaningful answers. Tom, that is not how science
works.
And no HONEST scientist would use those answers to attack that theory he
DISLIKE/HATES. Science is a dialog with Nature Tom.
Quote: in the physics community it is quite common to consider
one's understanding of a subject to be measured by the ability to
In the physics community it is rather common to provide detailed replies
when one is sure the other can understand it. One aloso usually ignores
unfair queries That is because you received that reply in
sci.physics.research.
Quote: Whyever would that matter? -- who cares about a demonstrably incorrect
and soundly refuted theory like NG?
"Yours is a statement of profound ignorance in all of its parts."
--- Uncle Al to Tom Roberts. Feb 2008
--
I apply http://canonicalscience.org/en/miscellaneouszone/guidelines.txt |
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| Eric Gisse |
| Posted: Sun Mar 09, 2008 7:18 am |
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On Mar 9, 8:13 am, "Juan R." González-Álvarez
<j...@canonicalscience.com> wrote:
Quote: Tom Roberts wrote on Sat, 08 Mar 2008 20:26:21 +0000:
Juan R. González-Álvarez wrote:
Tom Roberts wrote on Sat, 08 Mar 2008 02:11:31 +0000: Hmmm. Crizing a
non-relativistic theory because fails on relativistic regimes is very
old relativistic tactic but is clearly unfair.
Criticizing a non-relativistic theory for disagreeing with experiments
is not "unfair" at all.
English may be not your natural language.
I said
Criticizing a non-relativistic theory for disagreeing with relativistic
experiments is "unfair" at all.
Why? If a theory fails to account for experiment, it is a fault of the
theory.
Quote:
Sure perihelions for Mercury, the Shapiro time delay, bending of EM
radiation by the sun, and GPS operation contain relativistic effects,
if one takes the general meaning not just a kinematic meaning.
Hmm. The usual meaning of "relativistic effects" is that they are
important only for speeds approaching c (SR) or very strong fields (GR).
None of the experiments I mentioned have either.
Completely wrong. E.g. anomaly Mercury perihelion is explained by two
relativistic corrections.
A new and interesting way of misunderstanding relativity. Do explain
why you think there are two corrections.
Quote:
But since you only look to "how" instead "why" you lack understanding.
Nobody would imagine one can apply NG *outside* its range of validity
waiting adequate answer, unless that person does not understand
SCIENCE.
Ok. I'm not the one pushing NG, you are.
One of your usual FALSE accusations tactics. Read i exactly said.
[my list of experiments, totally corrupted and unreadable]
When one does that, one finds that for EVERY ONE of the experiments I
mentioned the NGvalue is so different from the experimental value that
NG is soundly refuted; the GR value is quite reasonable for all of them.
No SERIOUS scientist would apply a theory outside its range of
applicability waiting meaningful answers. Tom, that is not how science
works.
And no HONEST scientist would use those answers to attack that theory he
DISLIKE/HATES. Science is a dialog with Nature Tom.
...and no SERIOUS or HONEST scientist would use domains of application
as a shield to protect it against the observational fact that it is
wrong.
Quote:
in the physics community it is quite common to consider
one's understanding of a subject to be measured by the ability to
In the physics community it is rather common to provide detailed replies
when one is sure the other can understand it. One aloso usually ignores
unfair queries That is because you received that reply in
sci.physics.research.
Whyever would that matter? -- who cares about a demonstrably incorrect
and soundly refuted theory like NG?
"Yours is a statement of profound ignorance in all of its parts."
--- Uncle Al to Tom Roberts. Feb 2008
--
I applyhttp://canonicalscience.org/en/miscellaneouszone/guidelines.txt |
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| Albertito |
| Posted: Sun Mar 09, 2008 9:49 am |
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On 7 mar, 13:56, Eric Gisse <jowr...@gmail.com> wrote:
Quote: On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
On 6 mar, 23:02, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 6, 11:41 am, Albertito <albertito1...@gmail.com> wrote:
There are evidences showing that in Solar system,
the speed of gravity is many orders of magnitude higher
than the speed of light.
No, there is not. Just because you say so doesn't mean it is true.
But, what must we understand
by speed of gravity?. Aetherists often claim that gravity
are longitudinal waves, whereas light are transverse
waves through the aether.
Why even mention this? Ether has been ruled out as a viable concept
EVERY SINGLE TIME for the last hundred and thirty years. Nobody but
cranks in the fringe take ether seriously anymore.
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
We know that in any medium
longitudinal waves travel faster than transverse waves.
Only if the medium is anisotropic. Where are the calculations in which
you actually derive the things you write?
Wrong. Anisotropy is not a requirement for the speed of longitudinal
waves were higher than the speed of transverse ones. In isotropic
and homogenous medium that difference in speed holds too.
Show me the derivation.
[snip spew]
You are not listening. You write down a bunch of equations but you
don't justify or derive any of them.
Look at these equations,
c_L^2 = (2G/d_0)(1-v)/(1-2v)
c_S^2 = G/d_0
c_L is longitudinal speed
c_S is transverse speed,
d_0 is mass density,
G is G is shear modulus, and
v is Poison's ratio
For an isotropic medium, the Poison's ratio is the same
in any direction. Therefore, c_L = c_S only in the case
v = 0. This case can only occurs for a medium
which were perfectly compressible. So, it is clear
that the factor (1-v)/(1-2v) can only be greater or
equal to 1, yieding always c_L >= c_S. |
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| Albertito |
| Posted: Sun Mar 09, 2008 9:57 am |
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On 9 mar, 19:49, Albertito <albertito1...@gmail.com> wrote:
Quote: On 7 mar, 13:56, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
On 6 mar, 23:02, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 6, 11:41 am, Albertito <albertito1...@gmail.com> wrote:
There are evidences showing that in Solar system,
the speed of gravity is many orders of magnitude higher
than the speed of light.
No, there is not. Just because you say so doesn't mean it is true.
But, what must we understand
by speed of gravity?. Aetherists often claim that gravity
are longitudinal waves, whereas light are transverse
waves through the aether.
Why even mention this? Ether has been ruled out as a viable concept
EVERY SINGLE TIME for the last hundred and thirty years. Nobody but
cranks in the fringe take ether seriously anymore.
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
We know that in any medium
longitudinal waves travel faster than transverse waves.
Only if the medium is anisotropic. Where are the calculations in which
you actually derive the things you write?
Wrong. Anisotropy is not a requirement for the speed of longitudinal
waves were higher than the speed of transverse ones. In isotropic
and homogenous medium that difference in speed holds too.
Show me the derivation.
[snip spew]
You are not listening. You write down a bunch of equations but you
don't justify or derive any of them.
Look at these equations,
c_L^2 = (2G/d_0)(1-v)/(1-2v)
c_S^2 = G/d_0
c_L is longitudinal speed
c_S is transverse speed,
d_0 is mass density,
G is G is shear modulus, and
v is Poison's ratio
For an isotropic medium, the Poison's ratio is the same
in any direction. Therefore, c_L = c_S only in the case
v = 0. This case can only occurs for a medium
which were perfectly compressible. So, it is clear
that the factor (1-v)/(1-2v) can only be greater or
equal to 1, yieding always c_L >= c_S.
Sorry, I made a mistake, I meant c_L = c_S can only occur
in the case (1-v)/(1-2v) = 1/2. But, that case can't occur for
any real value of v. |
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| Eric Gisse |
| Posted: Sun Mar 09, 2008 10:16 am |
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Guest
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On Mar 9, 11:49 am, Albertito <albertito1...@gmail.com> wrote:
Quote: On 7 mar, 13:56, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
On 6 mar, 23:02, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 6, 11:41 am, Albertito <albertito1...@gmail.com> wrote:
There are evidences showing that in Solar system,
the speed of gravity is many orders of magnitude higher
than the speed of light.
No, there is not. Just because you say so doesn't mean it is true.
But, what must we understand
by speed of gravity?. Aetherists often claim that gravity
are longitudinal waves, whereas light are transverse
waves through the aether.
Why even mention this? Ether has been ruled out as a viable concept
EVERY SINGLE TIME for the last hundred and thirty years. Nobody but
cranks in the fringe take ether seriously anymore.
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
We know that in any medium
longitudinal waves travel faster than transverse waves.
Only if the medium is anisotropic. Where are the calculations in which
you actually derive the things you write?
Wrong. Anisotropy is not a requirement for the speed of longitudinal
waves were higher than the speed of transverse ones. In isotropic
and homogenous medium that difference in speed holds too.
Show me the derivation.
[snip spew]
You are not listening. You write down a bunch of equations but you
don't justify or derive any of them.
Look at these equations,
c_L^2 = (2G/d_0)(1-v)/(1-2v)
c_S^2 = G/d_0
You are, once again, missing the point. I want a derivation of these
equations from first principles.
Quote:
c_L is longitudinal speed
c_S is transverse speed,
d_0 is mass density,
G is G is shear modulus, and
v is Poison's ratio
For an isotropic medium, the Poison's ratio is the same
in any direction. Therefore, c_L = c_S only in the case
v = 0. This case can only occurs for a medium
which were perfectly compressible. So, it is clear
that the factor (1-v)/(1-2v) can only be greater or
equal to 1, yieding always c_L >= c_S. |
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| Albertito |
| Posted: Sun Mar 09, 2008 11:05 am |
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Guest
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On 9 mar, 20:16, Eric Gisse <jowr...@gmail.com> wrote:
Quote: On Mar 9, 11:49 am, Albertito <albertito1...@gmail.com> wrote:
On 7 mar, 13:56, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
On 6 mar, 23:02, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 6, 11:41 am, Albertito <albertito1...@gmail.com> wrote:
There are evidences showing that in Solar system,
the speed of gravity is many orders of magnitude higher
than the speed of light.
No, there is not. Just because you say so doesn't mean it is true.
But, what must we understand
by speed of gravity?. Aetherists often claim that gravity
are longitudinal waves, whereas light are transverse
waves through the aether.
Why even mention this? Ether has been ruled out as a viable concept
EVERY SINGLE TIME for the last hundred and thirty years. Nobody but
cranks in the fringe take ether seriously anymore.
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
We know that in any medium
longitudinal waves travel faster than transverse waves.
Only if the medium is anisotropic. Where are the calculations in which
you actually derive the things you write?
Wrong. Anisotropy is not a requirement for the speed of longitudinal
waves were higher than the speed of transverse ones. In isotropic
and homogenous medium that difference in speed holds too.
Show me the derivation.
[snip spew]
You are not listening. You write down a bunch of equations but you
don't justify or derive any of them.
Look at these equations,
c_L^2 = (2G/d_0)(1-v)/(1-2v)
c_S^2 = G/d_0
You are, once again, missing the point. I want a derivation of these
equations from first principles.
c_L is longitudinal speed
c_S is transverse speed,
d_0 is mass density,
G is G is shear modulus, and
v is Poison's ratio
For an isotropic medium, the Poison's ratio is the same
in any direction. Therefore, c_L = c_S only in the case
v = 0. This case can only occurs for a medium
which were perfectly compressible. So, it is clear
that the factor (1-v)/(1-2v) can only be greater or
equal to 1, yieding always c_L >= c_S.
From first principles? You're asking too much!
Even Einstein would be unable to derive the
speed of light from first principles!
You are kidding, aren't you? No, you do not want that.
You only want harassing. Although in this thread I realize
you are clueless, as usual. You are who is missing
the point here. |
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| Eric Gisse |
| Posted: Sun Mar 09, 2008 12:00 pm |
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On Mar 9, 12:05 pm, Albertito <albertito1...@gmail.com> wrote:
Quote: On 9 mar, 20:16, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 9, 11:49 am, Albertito <albertito1...@gmail.com> wrote:
On 7 mar, 13:56, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 7, 2:16 am, Albertito <albertito1...@gmail.com> wrote:
On 6 mar, 23:02, Eric Gisse <jowr...@gmail.com> wrote:
On Mar 6, 11:41 am, Albertito <albertito1...@gmail.com> wrote:
There are evidences showing that in Solar system,
the speed of gravity is many orders of magnitude higher
than the speed of light.
No, there is not. Just because you say so doesn't mean it is true.
But, what must we understand
by speed of gravity?. Aetherists often claim that gravity
are longitudinal waves, whereas light are transverse
waves through the aether.
Why even mention this? Ether has been ruled out as a viable concept
EVERY SINGLE TIME for the last hundred and thirty years. Nobody but
cranks in the fringe take ether seriously anymore.
What is spacetime but a kind of ether?
Spacetime in no way resembles ether. Learn what both the concepts
represent.
We know that in any medium
longitudinal waves travel faster than transverse waves.
Only if the medium is anisotropic. Where are the calculations in which
you actually derive the things you write?
Wrong. Anisotropy is not a requirement for the speed of longitudinal
waves were higher than the speed of transverse ones. In isotropic
and homogenous medium that difference in speed holds too.
Show me the derivation.
[snip spew]
You are not listening. You write down a bunch of equations but you
don't justify or derive any of them.
Look at these equations,
c_L^2 = (2G/d_0)(1-v)/(1-2v)
c_S^2 = G/d_0
You are, once again, missing the point. I want a derivation of these
equations from first principles.
c_L is longitudinal speed
c_S is transverse speed,
d_0 is mass density,
G is G is shear modulus, and
v is Poison's ratio
For an isotropic medium, the Poison's ratio is the same
in any direction. Therefore, c_L = c_S only in the case
v = 0. This case can only occurs for a medium
which were perfectly compressible. So, it is clear
that the factor (1-v)/(1-2v) can only be greater or
equal to 1, yieding always c_L >= c_S.
From first principles? You're asking too much!
Only if your skill set isn't up to the task, which it appears to be.
What I ask of you would be one problem out of a larger classical
mechanics problem set. You don't have to go through it all, just write
down the important parts.
Quote: Even Einstein would be unable to derive the
speed of light from first principles!
I'm asking you to derive or show references for your primary working
equations because I believe they can not be simultaneously true in an
isotropic medium, much less be a part of your larger agenda of
disproving SR.
Plus, Einstein would be able to do what you say he couldn't. Deriving
the speed of propagation for a medium is a homework exercise in both
classical E&M and mechanics.
Quote:
You are kidding, aren't you? No, you do not want that.
You only want harassing. Although in this thread I realize
you are clueless, as usual. You are who is missing
the point here.
I'm making some old Pentium 3 systems into cluster compute nodes. They
can't PXE, so I have to boot off a CD and do it the slow way. I'm
going to be here for a few hours while this churns, so I have nothing
better to do.
Your whole point is that - somehow, though you can't explain how - a
medium which not only supports transverse and longitudinal waves
manages to have speeds of propagation that are different despite being
isotropic. Then somehow - I have no idea how you do - you make the
assertion that this not only applies to the speed of gravity, which
you haven't justified, but that it applies to the speed of light as
well.
Even if your assertions about speeds of propagation were true [they
aren't], you have in no way substantiated the links you are making.
Science isn't about increasingly bold assertions - no matter how
absurd it looks to an outsider. |
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| Lady Chacha |
| Posted: Mon Mar 10, 2008 2:12 am |
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| Tom Van Flandern |
| Posted: Tue Apr 01, 2008 12:17 pm |
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Tom Roberts" <tjroberts137@sbcglobal.net> writes:
Quote: [Roberts]: In the model of GR, gravity does not propagate at all, but
changes in gravity propagate with speed c.
That is directly in contradiction to experiment and observations. Binary
pulsars are an obvious example, as I demonstrated (without any dissent) in
Reference B below. But even the simplest orbit computation program can show
the same thing. If you use light-time-retarded positions of bodies to
compute orbits, the computed orbits are open spirals, in contradiction to
observations.
But you've obviously never done the experiment yourself, or have used
only propagation delays in the potential field, which are irrelevant for
orbit computation. See Reference (C).
There is no way known to any person on this planet to avoid the
conclusion that gravitational force propagates >> c without invoking some
kind of physical miracle, such as an effect without a cause or the creation
of new momentum out of nothingness. Mathematical relativists don't seem
bothered by such miracles. Meanwhile, real world physicists know they must
not invoke miracles in their theories because that makes them
non-falsifiable, and therefore unscientific. [See Reference E.]
Quote: [Roberts]: The GR model agrees with all these "evidences", and indeed it
accounts MUCH more accurately than the Newtonian model for measurements in
the solar system (including the perihelia of Mercury and other planets,
the Shapiro time delay, the bending of EM radiation by the sun, the
operation of the GPS, the frame dragging measured by the LAGEOS
satellites, etc.).
True but irrelevant because GR is a field theory and describes only the
field. The gravitational potential field causes all the effects on your
list. But it does not cause ordinary orbital motion. Nor do the field
equations describe ordinary orbital motion. To get that, one must take a
gradient of the potential (or its equivalent) to get what you like to call
an "approximation" theory. In simple, classical physics lingo, that process
develops an expression for the 3-space (Euclidean) acceleration of bodies in
coordinate time, which gives the orbital motion, which is then compared
against astronomical observations made in Euclidean 3-space using proper
time clocks.
Try computing an orbit with GR just once in any system with at least two
significant masses, and you will discover that you cannot do it without
adopting near-infinite gravitational force propagation speed between bodies
applying forces to one another. Then the dawn will come, and you will
finally understand what the "speed of gravity" issue is about.
Quote: [Roberts]: it is MUCH better to discuss models and their agreement with
experiments than to discuss MODEL-DEPENDENT quantities like "speed of
gravity".
The "speed of gravity" is not a model-dependent concept except at the
level of parts per 100 million, any more than "perihelion motion" is
model-dependent. Its simple meaning is: When a source mass accelerates, the
speed of gravity is the ratio of the distance of a target body to the time
elapsed before the target body responds. And every known experiment measures
that elapsed interval to be zero within experimental error, making the speed
of gravity >> c and approximately infinite.
Relativists like to redefine the concept to refer to the speed of
changes in the gravitational potential field, which everyone agrees is c.
But that refers to gravitational waves, and avoids the issue of the
propagation speed of gravitational force for determining the ordinary
orbital motion of two masses around a common center of mass. One must either
give up the causal link to a source mass, or agree that the force propagates
from the source mass to the target body faster than c.
Quote: Tom Van Flandern does not understand the real issues, and uses egregious
PUNs to promulgate his claims. In particular, what he calls "speed" is not
what anybody else would call "speed". The experiments he cites do NOT
measure speed (usual meaning), and their actual measurements are fully
consistent with GR, in which nothing propagates faster than c.
Quit making up nonsense. The published papers are in references (A),
(B), (C), and (D) below. "Speed" has its unambiguous, classical meaning in
all of them, as the editors, reviewers, and readers have all understood.
Where are your publications on the subject?
Quote: [Juan]: For calculations of orbits we have to use the actual positions of
bodies and not the perceived locations.
[Roberts]: True in Newtonian mechanics; irrelevant in GR.
The comparison of theory with observations is not relevant? How absurd!
You are disconnected from reality.
References:
** (A) "Possible new properties of gravity", Astrophys.&SpaceSci.
244:249-261 (1996);
http://metaresearch.org/cosmology/gravity/possiblenewpropertiesofgravity.asp
** (B) "The speed of gravity - What the experiments say", Phys.Lett.A
250:1-11 (1998); http://metaresearch.org/cosmology/speed_of_gravity.asp
** (C) "Reply to comments on 'The speed of gravity'", Phys.Lett.A
262:261-263 (1999).
** (D) "Experimental Repeal of the Speed Limit for Gravitational,
Electrodynamic, and Quantum Field Interactions", T. Van Flandern and J.P.
Vigier, Found.Phys. 32:1031-1068 (2002); preprint under title "The speed of
gravity - Repeal of the speed limit" at
http://metaresearch.org/cosmology/gravity/speed_limit.asp
** (E) "Physics has its principles", in Gravitation, Electromagnetism and
Cosmology, K. Rudnicki, ed., C. Roy Keys Inc., Montreal, 87-101 (2001);
http://metaresearch.org/cosmology/PhysicsHasItsPrinciples.asp
Tom Van Flandern - Sequim, WA - see our web site on frontier astronomy
research at http://metaresearch.org |
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| Koobee Wublee |
| Posted: Tue Apr 01, 2008 12:51 pm |
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On Apr 1, 10:17 am, "Tom Van Flandern" wrote:
Quote: Tom Roberts" <tjroberts...@sbcglobal.net> writes:
[Roberts]: In the model of GR, gravity does not propagate at all, but
changes in gravity propagate with speed c.
That is directly in contradiction to experiment and observations. Binary
pulsars are an obvious example, as I demonstrated (without any dissent) in
Reference B below. But even the simplest orbit computation program can show
the same thing. If you use light-time-retarded positions of bodies to
compute orbits, the computed orbits are open spirals, in contradiction to
observations.
But you've obviously never done the experiment yourself, or have used
only propagation delays in the potential field, which are irrelevant for
orbit computation. See Reference (C).
There is no way known to any person on this planet to avoid the
conclusion that gravitational force propagates >> c without invoking some
kind of physical miracle, such as an effect without a cause or the creation
of new momentum out of nothingness. Mathematical relativists don't seem
bothered by such miracles. Meanwhile, real world physicists know they must
not invoke miracles in their theories because that makes them
non-falsifiable, and therefore unscientific. [See Reference E.]
While Professor Roberts is struggling to understand how a binary
system still have to account for gravitational field varying with
time, Professor Carlip addressed your claim that the speed of gravity
being several billion times the speed of light in the following
article. I have seen no public refutation to his work.
http://arxiv.org/abs/gr-qc/9909087
The aberration can also be simply explained by the good old Galilean
transformation. Any apparent distance must be corrected by the
Galilean transform. In this paper, Professor Carlip is suggesting the
gravitational distance between the stars must be corrected by this
aberration. In doing so, it will cause a first-order cancellation on
the issue of the speed of gravity. The argument between you and him
centers around if the aberration must be corrected. Do you have any
fundamental argument to suggest that the aberration should not be
corrected in this case? |
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| Juan R." González-Álvarez |
| Posted: Wed Apr 02, 2008 12:35 am |
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Koobee Wublee wrote on Tue, 01 Apr 2008 15:51:36 -0700:
Quote: Professor Carlip addressed your claim that the speed of gravity being
several billion times the speed of light in the following article. I
have seen no public refutation to his work.
http://arxiv.org/abs/gr-qc/9909087
As pointed several times in this newsgroup Carlip is wrong about
interactions.
Carlip paper received a formal reply by van Flandern on:
Experimental Repeal of the Speed Limit for Gravitational, Electrodynamic,
and Quantum Field Interactions. 2002: Found. Phys. 32, 1031. Van
Flandern, T; Vigier, J.P.
First part of Carlip paper is a 'review' about electromagnetism. Carlip
mistaken claims about retarded electromagnetic interactions were
corrected in a number of papers. See for instance,
Necessity of simultaneous co-existence of instantaneous and retarded
interactions in classical electrodynamics. 1999: Int. J. of Mod. Phys. A
14(24), 3789. Chubykalo, Andrew E; Vlaev, Stoyan J.
Carlip mistakes about electromagnetic fields and nonrelativistic limit of
interactions have been also corrected in other published works.
In all papers, the conclusions are that electromagnetic interactions are
not retarded by c.
Actually i am finishing a draft on foundational issues of Chubykalo
dualism, the work includes an extension of dualism to gravitational
interactions.
The conclusion is again that gravitational interactions are *not*
retarded by c (as one would wait). Several mistakes of Carlip paper
(section on gravitation) are highlighted.
Of course, the model of retarded interactions of GR arises as a well
defined limit but it is not a fundamental model of interactions but one
of limited aplicability.
--
http://canonicalscience.org/en/miscellaneouszone/guidelines.txt |
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| Juan R." González-Álvarez |
| Posted: Wed Apr 02, 2008 12:50 am |
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"Juan R." González-Ãlvarez wrote on Wed, 02 Apr 2008 12:35:26 +0200:
Quote: The conclusion is again that gravitational interactions are *not*
retarded by c (as one would wait). Several mistakes of Carlip paper
(section on gravitation) are highlighted.
I mean that gravitational interactions are *not* retarded by c (as one
would wait in basis to recent works proving that electromagnetic
interactions are not retarded indeed).
--
http://canonicalscience.org/en/miscellaneouszone/guidelines.txt |
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| Koobee Wublee |
| Posted: Wed Apr 02, 2008 6:21 pm |
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On Apr 2, 3:35 am, "Juan R." González-Álvarez wrote:
Quote: Koobee Wublee wrote on Tue, 01 Apr 2008 15:51:36 -0700:
Professor Carlip addressed your claim that the speed of gravity being
several billion times the speed of light in the following article. I
have seen no public refutation to his work.
http://arxiv.org/abs/gr-qc/9909087
As pointed several times in this newsgroup Carlip is wrong about
interactions.
Carlip paper received a formal reply by van Flandern on:
Experimental Repeal of the Speed Limit for Gravitational, Electrodynamic,
and Quantum Field Interactions. 2002: Found. Phys. 32, 1031. Van
Flandern, T; Vigier, J.P.
Yes, I found it in his website now. So, after Professor turned Dr.
Van Flandern's claim of infinite speed of gravity on its head, Dr. Van
Flandern reversed the favor by turning Professor Carlip's claim in
aberration of gravity on its very own head. It looks like Professor
Carlip has somehow ignored the speed of one star in his aberration
consideration. Has Professor Carlip offered any graceful retreat from
that mistake? |
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