New answers tagged time-travel
If you define "now" to be all those points in space and time that have hypothetical, pre-synchronized, stationary clocks that read the same time as your clock, then there "currently" exists a hypothetical observer somewhere, who is moving relative to us, for whom "now" includes Earth, circa 1900. But these notions of "now" are different for the two ...
The first statement is very much true. Light moves a finite, if very fast, speed. Even ignoring any movement/ relativistic effects this simply means that observers closer to earth will see it in it's most recent state. It may sound strange for light, but we see exactly the same phenomenon in sound, an observer noticeably closer to the source of a sound will ...
No. Not that we know of unless we change the current laws of physics to allow faster than light travel or imaginary mass
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