Re:Einstein, Symmetry and the Future of Physics
by mr_mitm on Thursday June 27, 2019 @04:02AM
(#20292529)
> This isn't quite right. Energy isn't conserved in General Relativity.
Correct, and the reason is that in GR there is (in general) no time translation invariance. The associated conserved quantity to time translation invariance is precisely what we call "energy". In our universe this manifests as the expansion of spacetime.
Correct, and the reason is that in GR there is (in general) no time translation invariance. The associated conserved quantity to time translation invariance is precisely what we call "energy". In our universe this manifests as the expansion of spacetime.
More on this: https://www.preposterousuniverse.com/blog/2010/02/22/energy-...