Ivanenko, Logunov and even Zelmanov

[Carlos L. Janer]

What do you think about the work done by these Russians to give alternative formulations to General Relativity?

 

[litup]

Do we get a link?

 

[Carlos L. Janer]

Do we get a link?

I don't think they're going to be be terribly useful, but here you have them:

https://en.wikipedia.org/wiki/Dmitri_Ivanenko
https://en.wikipedia.org/wiki/Anatoly_Logunov
https://en.wikipedia.org/wiki/Abraham_Zelmanov

You can (legally) download some of their books in English for free.

 

[Ibix]

The second link in "similar discussions" is https://www.physicsforums.com/threads/abraham-zelmanovs-chronometric-invariants.164305/

 

[Thinkor]

What do you think about the work done by these Russians to give alternative formulations to General Relativity?

At the link

https://archive.org/details/LogunovMestvirishviliTheRelativisticTheoryOfGravitation

you will find The Relativistic Theory of Gravitation by Logunov and Mestvirishvili, translated into English. It is a difficult read, but more readable than many serious books on gravitation. Unfortunately, it was a little beyond my endurance.

 

[PeterDonis]

What do you think about the work done by these Russians to give alternative formulations to General Relativity?

I'm not sure I would call this work an alternative formulation of GR. I don't think that was the authors' intention either. I think their intention was to give an alternative theory of gravity, in competition with GR. This work is not considered mainstream. I'm not familiar enough with it to know how much its predictions differ from those of GR, or how they compare to experimental tests.

 

[Thinkor]

Logunov's RTG is definitely a different theory than GR. You can get a good idea of how it differs by reading the one page preface and six page introduction. In the introduction, citing Hilbert, it is claimed "that GR in principle cannot have laws of energy-momentum and angular momentum ... Even today there are scientists that do not understand this, while others do understand it but interpret it as the most important step made by GR, a step that overthrew the concept of energy. ... [In] GR the gravitational field energy cannot be localized. But that absence of any localization of field energy and the absence of conservation laws lead to the absence of the concepts of gravitational waves and gravitational wave flux, which means that the propagation of gravitational energy in space from one object to another is impossible in GR." In the preface it is also claimed, regarding this point, "Einstein's formula (15.56) for gravitational waves does not follow from GR." This reminds me of Einstein's basically correct explanation of the clock paradox in SR, although SR, at that time, applied only to unaccelerated motion; his intuition outran his principles.

 

[Ilja]

I'm not sure I would call this work an alternative formulation of GR. I don't think that was the authors' intention either. I think their intention was to give an alternative theory of gravity, in competition with GR. This work is not considered mainstream. I'm not familiar enough with it to know how much its predictions differ from those of GR, or how they compare to experimental tests.

Logunov's Relativistic Theory of Gravity (RTG) is an alternative theory of gravity, with a massive graviton.

But in the case you set the graviton mass zero, the equations become the Einstein equations with zero cosmological constant in harmonic gauge. So, this particular case can be considered as an alternative interpretation of GR, but it would be more accurate to name it an alternative interpretation of the Einstein equations of GR. Because even in this limit there remain differences. So, a solution is complete if it is defined for all values of the preferred background coordinates. But from point of view of GR this can be incomplete. Then, there is a causality condition, which connects the Einstein causality of the gravitational field with a preferred Minkowski background metric. This forbids some GR solutions, in particular those with closed causal loops.

With nonzero graviton mass, the predictions differ a lot. The FLRW universe becomes cyclic, there appear stable frozen stars with a radius slightly greater than horizon size. But I'm not aware of decisive conflicts with observation. The candidate for this would be the wrong sign of the cosmological constant. But with Wiltshire's timescape cosmology this would not be problematic too.