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Re: Arch and scaffold: How Einstein found his field equations

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Sam Wormley wrote:

> Arch and scaffold: How Einstein found his field equations
>> http://scitation.aip.org/content/aip/magazine/physicstoday/
article/68/11/10.1063/PT.3.2979?utm_source=Physics%
20Today&utm_medium=email&utm_campaign=6339900_Physics%20Today%3A%20The%
20week%20in%20Physics%2026-30%20October&dm_i=1Y69,3RVWC,E1PPN7,DLFXW,1
> 
> 
>> In his later years, Einstein often claimed that he had obtained the
>> field equations of general relativity by choosing the mathematically
>> most natural candidate. His writings during the period in which he
>> developed general relativity tell a different story.

Hahahahaaa

>> Page proofs of Hilbert’s paper, which was not published until March
>> 1916, surfaced in the late 1990s. An analysis of them14 shows that
>> Einstein need not have worried about Hilbert in November 1915. In
>> important ways, the theory presented in the page proofs is closer to
>> the Entwurf theory than to general relativity in its final form. It has
>> the same structure as the version of the Entwurf theory published in
>> the review article of November 1914. It is true that Hilbert chose as
>> his Lagrangian the Riemann curvature scalar, which is the gravitational
>> part of the Lagrangian for the generally covariant Einstein field
>> equations. At that point, however, Hilbert accepted Einstein’s hole
>> argument against generally covariant field equations and imposed a
>> coordinate restriction via a relation he suggestively called the energy
>> theorem. So the actual field equations in the page proofs are not
>> generally covariant. The restriction was dropped in the published
>> version of the paper.

hahahaha, thanks.

>> Despite Einstein’s efforts to hide the scaffold, the arch unveiled in
>> the first November paper still shows clear traces of it. Einstein
>> wanted to display its mathematical splendor, but his structure was not
>> quite up to code yet. To prevent a violation of energy–momentum
>> conservation from bringing it down, he had to prop it up with some
>> lumber from the Entwurf scaffold, a support beam cut to the size of
>> unimodular transformations. Unfortunately, that support beam did not
>> leave enough room for another critical piece of scaffolding, the
>> restriction to unimodular coordinates. Only with that restriction in
>> place could one fully appreciate the magnificence of the arch as a
>> structure that looks the same from all angles even though during
>> construction it could only be viewed from some. To make room for
>> unimodular coordinates, Einstein brought in the heavy machinery of the
>> electromagnetic worldview, then realized he did not need it. What he
>> needed instead was an extra term on the right-hand side of the field
>> equations with the trace of the energy–momentum tensor. That trace term
>> turned out to be the keystone of his arch.

hihihihii

>> That is how Einstein left the construction site in November 1915.
>> During the next few months, he cleared away the debris of the first two
>> November 1915 papers, which resulted in the first self-contained
>> exposition of the new theory, published in May 1916 (CPAE 6; 30).15 In
>> November 1916 he finally lifted the restriction to unimodular
>> coordinates (CPAE 6; 41). The arch was self-supporting at last, a
>> marvelous sight to behold for generations of physicists to come.

He was about to step in the Divergent Matter region, and got frightened. 
They we barely accept a curved spacetime, but a Divergent Matter they 
never would accept especially in those day.

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Arch and scaffold: How Einstein found his field equations Sam Wormley <swormley1@gmail.com> - 2015-11-02 10:31 -0600
  Re: Arch and scaffold: How Einstein found his field equations gilber34 <fafa@invalid.com> - 2015-11-02 10:57 -0600
  Re: Arch and scaffold: How Einstein found his field equations Jeffrey Bannister <jbann@highadvancedscience.org> - 2015-11-02 19:41 +0000
  Re: Arch and scaffold: How Einstein found his field equations Fabian Russell <root@localhost.localdomain> - 2015-11-02 20:07 +0000
    Re: Arch and scaffold: How Einstein found his field equations xxein1@att.net - 2015-11-04 18:11 -0800
      Psalms 46 noTthaTguY <abu.kuanysh05@gmail.com> - 2015-11-05 20:08 -0800
  Re: Arch and scaffold: How Einstein found his field equations "Y.Porat" <y.y.porat@gmail.com> - 2015-11-06 05:23 -0800
    languages of the mother tongue(s noTthaTguY <abu.kuanysh05@gmail.com> - 2015-11-07 18:17 -0800

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