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Distance and Time

  1. Aug 24, 2010 #1
    I'm new here and my question could sound stupid but I'm a little bit confused.

    The Big Bang did happen 13.6 billion years ago. The Universe burst into life and after a while stars burst into life. Some of these stars are close to Earth like Sun and some of them are far far away.

    Let's say one of them is 5 million light years away. That means what we see is actually what that star looked like 5 million years ago.It may be not there now, right? Let's say I saw an object which is 13.5 billion light years away. Does that mean I'm seeing something which belongs to the early Universe?
     
  2. jcsd
  3. Aug 24, 2010 #2
    Yes, exactly.
     
  4. Aug 24, 2010 #3
    So let me get this stragiht if I would see an object which is 13.6 billion light years away, that would probably be the Big Bang?

    There is still some unresolved paradox here. Let's say I saw two objects one of them is 13,6 billion light years away the other one is 6 billion light years away. For me the first object would be the beginning of time. However as for the second object it would be something which is 7,7 billion light years away, it wouldn't mean the beginning of time and space.
     
  5. Aug 24, 2010 #4
    Basically; you would be seeing something soon after the big bang, yes.


    I'm sorry, I don't understand what you mean.
     
  6. Aug 24, 2010 #5
    What I'm saying is basically when I see an "object" 13,6 billion light years away it is the Big Bang. But the second object is close to the first "object". So the distance between them is just 7,6 billion light years. So let's say that second object is a planet. If people on that planet see the first "object" for them that is not the Big Bang.
     
  7. Aug 24, 2010 #6
    No, it would still be 'the big bang.' The people on the 'planet' are looking back at the big bang 6 billion years ago, when the big bang was closer (spatially and temporally) to them.
     
  8. Aug 24, 2010 #7
    Got it, thanks :)
     
  9. Aug 24, 2010 #8
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