In those scales (cosmology+Field Theory) energy is derived and defined as the "t...

btilly · 2025-02-09T20:19:21 1739132361

As much as we want time symmetry, we still live in an expanding universe. So we have at least some asymmetry.

Iolaum · 2025-02-09T20:26:35 1739132795

Time symmetry applies to the physical laws governing the universe, not the distribution of mass in it.

For a simpler example look at Newton's 3 laws. They have time symmetry but still allow for things to move around!

btilly · 2025-02-09T21:13:46 1739135626

It also doesn't apply to the structure of space-time. Which is not a situation that Newton's laws can deal with.