Exploring General Theory of Relativity

Click For Summary

Discussion Overview

The discussion explores the General Theory of Relativity (GR) and the possibility of obtaining accurate results without relying on the concept of four-dimensional curved space. Participants examine alternative formulations and interpretations of GR, including their implications for predictions and experimental outcomes.

Discussion Character

  • Exploratory, Debate/contested, Technical explanation

Main Points Raised

  • One participant questions the necessity of four-dimensional curved space for accurate results in GR.
  • Another participant asserts that Riemannian spacetime is essential for deriving the Einstein field equations.
  • A reference is made to a version of GR that maintains equivalent predictions to standard GR while describing spacetime as flat, suggesting that matter deforms measuring devices instead of curving spacetime.
  • A participant mentions an early quantum theory of gravity that could reproduce GR predictions by quantizing deviations from a flat metric.
  • Field Theory Gravity (FTG) is presented as a model that describes gravity as a tensor field in Minkowski space, with a reference to a discussion by Y. Baryshev, who claims FTG and GR may yield different predictions in high-energy scenarios.

Areas of Agreement / Disagreement

Participants express differing views on the necessity of curved spacetime in GR, with some supporting its essential role while others propose alternative models. The discussion remains unresolved regarding the equivalence of these models and their implications.

Contextual Notes

There are limitations regarding the assumptions made about the nature of spacetime and gravity in the proposed alternative theories, as well as the dependence on specific definitions of terms like "curvature" and "flatness." The implications of high-energy predictions remain unclear.

sharma_satdev
Messages
33
Reaction score
0
is it possible to get accurate results of general theory of relativity without retaining the concept of four dimensional curved space
 
Physics news on Phys.org
sharma_satdev said:
is it possible to get accurate results of general theory of relativity without retaining the concept of four dimensional curved space

GR makes use of Riemannian spacetime and without it, no one is able to obtain Einstein field equations!

AB
 
"Black holes and time warps: Einstein's outrageous legacy" mentions a version of GR that's equivalent to standard GR (in the sense that it makes the same predictions about experiments), but describes spacetime as flat. In this theory, matter doesn't curve spacetime, it deforms measuring devices.

I also think that one of the early attempts at a quantum (field) theory of gravity could accurately reproduce the predictions of GR. (Split the metric into a flat part plus the deviation from flatness, g=η+h, quantize only h, and throw away all Feynman diagrams that contain loops).
 
'Field Theory Gravity' models gravity as a tensor field in Minkowski space. There's a good discussion by Y. Baryshev in arXiv:gr-qc/9912003 v1 (1 Dec 1999). It is generally believed that FTG is identical to GR but Baryshev disputes this and claims they make different predictions in the high-energy regime.
 

Similar threads

Undergrad GR as Gauge Theory
  • · Replies 2 ·
Replies
2
Views
2K
Undergrad Robert B. Laughlin (Physics Nobel Laureate, Stanford University)
  • · Replies 6 ·
Replies
6
Views
2K
Undergrad Explore Spacetimes, Metrics & Symmetries in Relativity Theory
  • · Replies 7 ·
Replies
7
Views
3K
Undergrad Relativity: the Special and General theories
  • · Replies 10 ·
Replies
10
Views
2K
Graduate A global energy conservation law in general relativity
  • · Replies 36 ·
2
Replies
36
Views
2K
Undergrad Linearized Gravity: Bimetric Theory of General Relativity?
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Is Fatio–Le Sage's theory of gravitation an entropic gravity?
  • · Replies 33 ·
2
Replies
33
Views
3K
Undergrad Why Does Special Relativity Not Contradict General Philosophy?
  • · Replies 1 ·
Replies
1
Views
1K
Undergrad Does the metric in general relativity depend only on position because of the equivalence principle?
  • · Replies 16 ·
Replies
16
Views
2K
Graduate Decomposing Rank-2 Tensors in Dirac's "General Theory of Relativity
  • · Replies 5 ·
Replies
5
Views
2K