- #1
binbagsss
- 1,254
- 11
So from a killing tensor the FRW metric is known to possess, for a massless particle we find the well known result that as the universe expands the frequency of the photons decreases . But , what does this do for gr ?
Was this known to happen before gr ?
Thanks a lot.
(I know it is used to show the universe is expanding etc but is it any sort of test for gr ? )
Was this known to happen before gr ?
Thanks a lot.
(I know it is used to show the universe is expanding etc but is it any sort of test for gr ? )