In theory can entities in future spacetime look "back in time" to us, as we look back in time to other entities light years away, or is time simply a function of the distance and distance determines the relative time of all entities in relation to one another?
1 Answer
An entity that is 100 light-years away from us sees us as we were 100 years prior, and we see them as they were 100 years earlier as well. It is simply a matter of the finite speed of light, and the distance between the observer and the observed.
-
$\begingroup$ Should it be noted that this isn't a consequence of special relativity? $\endgroup$ Apr 5, 2019 at 21:32
-
$\begingroup$ Perhaps. But the OP didn't make the explicit connection so neither did I. $\endgroup$ Apr 6, 2019 at 5:10