I was just wondering that We see objects thru our eyes and light has to reach our eyes so that our brain can process that light.

But then there must be a time difference between that object which I see and me, as light has to travel from that object to me, let us assume the difference is in milliseconds.

Does that mean that every object I see, is past in time?


Yes, ofcourse the sun we see is nearly 8.30 minutes old(which is very far from us). Though objects near you say 1m apart are $t=1/3*10^{-8}$ seconds old, (roughly a nanosecond).The stars you see (the light coming from them ) which are billions light years away are the past . Who knows maybe they are not even there now?

  • $\begingroup$ then it means that if go faster than light we can manipulate the past? $\endgroup$ – nnd May 25 '19 at 8:02
  • $\begingroup$ we can only travel to future and not past .It's just theoretical $\endgroup$ – Bhavay May 25 '19 at 8:08
  • $\begingroup$ but if we can travel faster than light we can travel to the past and then come back to the present from the viewer's perspective the viewer will see the altered future. But it also means I changed the future of it but later when i see it it will be a past $\endgroup$ – nnd May 25 '19 at 9:32
  • $\begingroup$ Stars that are visible to the naked eye are in this galaxy, they aren't billions of light years away. We can see some stars that are a few thousand light years away, most visible stars are closer. See atlasoftheuniverse.com $\endgroup$ – PM 2Ring May 26 '19 at 2:28

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