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Viewing the Big Bang?

  1. Apr 19, 2005 #1
    I'm new here, people, so please forgive my ignorance. I don't study physics or astronomy - I'm just a closet AstroGeek if you will.

    Here's my dilemma:

    I'm comfortable with the idea of being able to "see" the Big Bang via telescope because the light we're seeing originated 30+ billion light years ago.

    What confuses me is in order for us to see the Big Bang from where we are, we must have arrived where we are before the light could get here. So in essence we were here 30+ billion light years before the light got here.

    Now if it's impossible to travel faster than the speed of light how can we possibly be looking back at the Big Bang?

    If we really are looking at the Big Bang, does it appear to be moving towards us or away from us?

    Since we can see the Big Bang we obviously know which direction it is coming from. If we were to travel towards the light from the Big Bang at 99% the speed of light at around 15 billion years we would presumably meet the light dead on. If we were to keep travelling in our direction allowing the light to pass us, would we no longer see anything in front of us? And what we would see when we turned around? Nothing?

    - Toby
  2. jcsd
  3. Apr 19, 2005 #2


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    The big bang is not thought of as an explosion of matter outward from a central point in space, it's space itself that has been expanding, like a chessboard where all the squares keep getting larger all at once, while the pieces centered on each square stay the same size--if you run this backwards, the pieces get scrunched closer and closer together as the squares shrink, and in the same way the density of all the matter and energy in the universe gets higher and higher as you approach the big bang. So light from the time of the big bang would originate from all locations in space, not from a single central explosion.
    Last edited: Apr 19, 2005
  4. Apr 19, 2005 #3


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    Hi Toby! Welcome to PF. While it is impossible for matter to travel faster than light, space itself is not forbidden to expand faster than the speed of light. Peruse through this [Ned Wright's cosmology tutorial] and see what you think:
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