time dilation

Discovery that quasars don't show time dilation mystifies astronomers

The phenomenon of time dilation is a strange yet experimentally confirmed effect of relativity theory. One of its implications is that events occurring in distant parts of the universe should appear to occur more slowly than events located closer to us.

However, a new study has found that this doesn’t seem to be the case - quasars, it seems, give off light pulses at the same rate no matter their distance from the Earth, without a hint of time dilation.

from PhysOrg.com