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The Motion of the Perihelion of Mercury



 
 
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  #1  
Old December 28th 08, 11:49 PM posted to sci.physics,sci.physics.relativity,sci.astro
[email protected]
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Default The Motion of the Perihelion of Mercury

THE MOTION OF THE PERIHELION OF MERCURY
In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.

What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?

Have any done these calculations?

Best regards
Louis Nielsen
Denmark


  #2  
Old December 29th 08, 12:16 AM posted to sci.physics,sci.physics.relativity,sci.astro
Androcles[_8_]
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Default The Motion of the Perihelion of Mercury


wrote in message
...
THE MOTION OF THE PERIHELION OF MERCURY
In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.

What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?


Different for each orbit as Venus, Earth and Jupiter advance.

Have any done these calculations?


Le Verrier, who had no computer.




  #3  
Old December 29th 08, 07:40 AM posted to sci.physics,sci.physics.relativity,sci.astro,fr.sci.physique,fr.sci.astrophysique
Pentcho Valev
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Default The Motion of the Perihelion of Mercury

On Dec 29, 12:49*am, wrote:
THE MOTION OF THE PERIHELION OF MERCURY
In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.

What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?

Have any done these calculations?

Best regards
Louis Nielsen
Denmark


As fas as I know, the only person dealing explicitly and honestly with
this is the French astrophysicist Jean-Marc Bonnet-Bidaud. Einstein
has made his calculations on the assumption that the mass of the sun
is perfectly spherical, and if it is not, the confirmation of
relativity becomes in fact a refutation:

http://astronomy.ifrance.com/pages/g.../einstein.html
"Le deuxième test classique donne en revanche des inquiétudes.
Historiquement, pourtant, l'explication de l'avance du périhélie de
Mercure, proposé par Einstein lui-même, donna ses lettres de noblesse
à la relativité générale. Il s'agissait de comprendra pourquoi le
périhélie de Mercure ( le point de son orbite le plus proche du
soleil ) se déplaçait de 574 s d'arc par siècle. Certes, sur ces 574
s, 531 s'expliquaient par les perturbations gravitationnels dues aux
autres planètes. Mais restait 43 s, le fameux effet "périhélique"
inexpliqué par les lois de Newton. Le calcul relativiste d'Einstein
donna 42,98 s ! L'accord et si parfait qu'il ne laisse la place à
aucune discussion. Or depuis 1966, le soleil est soupçonné ne pas être
rigoureusement sphérique mais légèrement aplati à l'équateur. Une très
légère dissymétries qui suffirait à faire avancer le périhélie de
quelques secondes d'arc. Du coup, la preuve se transformerait en
réfutation puisque les 42,88 s du calcul d'Einstein ne pourrait pas
expliquer le mouvement réel de Mercure."

More explanation he

http://www.cieletespaceradio.fr/inde...-des-sciences-
les-preuves-de-la-relativite
(ECOUTEZ!)

Pentcho Valev

  #4  
Old December 29th 08, 08:00 AM posted to sci.physics,sci.physics.relativity,sci.astro
Peter Webb[_2_]
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Posts: 927
Default The Motion of the Perihelion of Mercury


wrote in message
...
THE MOTION OF THE PERIHELION OF MERCURY
In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.

What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?

Have any done these calculations?

Best regards
Louis Nielsen
Denmark


AFAIR, the best experimental evidence we have is good to only a couple of
decimal places. I think we can dispense with the planets pretty quickly.
Venus weighs 1/500,000 of Sun, and that's the nearest one. Effects from the
Sun being oblate you would have to imagine are at least 2nd or 3rd order,
and its not very oblate at all.

Long and short is that measuring these effects would be experimentally
impossible, I bet.


  #5  
Old December 29th 08, 08:07 AM posted to sci.physics,sci.physics.relativity,sci.astro
Koobee Wublee
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Default The Motion of the Perihelion of Mercury

On Dec 28, 2:49 pm, wrote:

THE MOTION OF THE PERIHELION OF MERCURY


In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.


In an actual observation of Mercury’s orbital advance, there are
5,600” (in arc-seconds) per century of observed perihelion advance.
Among these, 5,025” are due to the 22,000-year precession of earth’s
orbital around the second. 532” were accounted for through inclusion
of other planets. That leaves (5,600” – 5,015” = 43”) unaccounted
for.

I suspect this 5,600” per century of perihelion advance is not very
accurate in the first place. I want to see error bars associated with
this experiment. Tell me if that is too much to ask.

What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?


The 43” was calculated based on Paul Gerber’s work. Other
mathematical methods do not yield the same result. shrug

Have any done these calculations?


There are at least 12 such calculations to predict Mercury’s orbital
advance in which the spacetime with the Schwarzschild metric is just
one of them according to Gerber’s method. shrug
  #6  
Old December 29th 08, 09:27 AM posted to sci.physics,sci.physics.relativity,sci.astro
Eric Gisse
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Default The Motion of the Perihelion of Mercury

On Dec 28, 1:49*pm, wrote:
THE MOTION OF THE PERIHELION OF MERCURY


No need to repeat the title twice, we can read.

In his general relativity calculation of the motion of the perihelion
of Mercury Albert Einstein had only taken into account the
gravitational actions between the Sun and the Mercury, which he also
assumed as two points.


Entirely correct.


What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?


Unknown to me, but I haven't done a literature search.

The classical analysis for Mercury's perihelion precession is almost
completely explained using perturbation theory, from the effects of
other planets. There is no reason - except for it being hard - that
the analysis can't be replicated while taking into account effects
from the other planets.

However, the effect between the Sun and Mercury is sufficient to
explain what is observed. There's a breakdown in MTW, by the way.


Have any done these calculations?

Best regards
Louis Nielsen
Denmark


  #7  
Old December 29th 08, 09:30 AM posted to sci.physics,sci.physics.relativity,sci.astro
Eric Gisse
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Posts: 1,465
Default The Motion of the Perihelion of Mercury

On Dec 28, 10:07*pm, Koobee Wublee wrote:
[...]

I suspect this 5,600” per century of perihelion advance is not very
accurate in the first place. *I want to see error bars associated with
this experiment. *Tell me if that is too much to ask.


Is reading the literature too much to ask?


What will be, according to the theory of general relativity, the value
of the motion of the perihelion of Mercury if the gravitational
actions of all the planets in the solar system are taken into account
and also it is taken into account that the Sun is a little oblate?


The 43” was calculated based on Paul Gerber’s work. *Other
mathematical methods do not yield the same result. *shrug


No, it was not "based on Paul Gerber's work". All Gerber did was guess
the form of a velocity-dependent potential that would give the same
effects. The actual analysis was based on the works of Le Verrier.

Do you have a literature reference for the assertion that other
methods "do not yield the same result", or is this more of your
typical nonsense that has no scholarly backing?

[...]
  #8  
Old December 29th 08, 12:15 PM posted to sci.physics,sci.physics.relativity,sci.astro
Ian Parker
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Posts: 2,554
Default The Motion of the Perihelion of Mercury

On 29 Dec, 08:27, Eric Gisse wrote:

Have any done these calculations?


Best regards
Louis Nielsen
Denmark- Hide quoted text -


http://www.smad.com/analysis/hpop.htm

You can actually download the program if you want to. Answer is
emphatically yes. Inceased accuracy is in fact serving to confirm GTR.


- Ian Parker
  #10  
Old December 29th 08, 05:10 PM posted to sci.physics,sci.physics.relativity,sci.astro
Strich.9[_2_]
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Posts: 31
Default The Motion of the Perihelion of Mercury

On Dec 29, 10:35 am, Uncle Al wrote:

Einstein was correct.


Uncle Al recites his prayers daily.
 




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