All Questions
5
questions
3
votes
3
answers
84
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Newton's approximation of 2+1D gravity
I learnt that the curvature tensor in 2+1D spacetime is zero in vacuum. How is it possible to come from there to the Newton's theory in 2D + time, where I guess, the gravitational force law is still ...
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2
votes
0
answers
107
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Would General Relativity work if gravity were not an inverse square law? [duplicate]
I understand that General Relativity explains gravity by framing it as a consequence of the curvature of spacetime rather than as a force. Does this theoretically guarantee that gravity must be an ...
- 21
5
votes
1
answer
277
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General relativity modifies Newton's inverse square law of gravity. Why do many people do experiments to test the inverse square law?
General relativity may induce the so-called post-Newtonian correction to the inverse square law of gravity. For details, please refer to chapter 9 of Weinberg's Gravitation and Cosmology.
However, ...
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9
votes
2
answers
2k
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Gravity in 2+1D spacetime and inverse linear law
In our 3+1D universe, gravity obeys the inverse square law. In a 4+1D universe, gravity would be expected to obey the inverse cube law et cetera.
In a 2+1D universe, one would similarly expect gravity ...
- 281
2
votes
2
answers
697
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Newton's Law of Gravitation, Gauss Law and GR
From One of My Unpublished Papers
$$\frac{d^2 x^{\alpha}}{d\tau^2}=-\Gamma^{\alpha}_{\beta \gamma}\frac{dx^{\beta}}{d\tau}\frac{dx^{\gamma}}{d\tau} \tag{1}$$
For radial motion in Schwarzschild’s ...
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