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Can we see big bang in future?

  1. Mar 13, 2012 #1


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    Suppose we developed a technology, which is very necessary, that we could travel FTL. Can we reach a point in cosmos from where both the chronological and spatial distance of big bang is same. Will then we be able to see bang happening?
  2. jcsd
  3. Mar 13, 2012 #2
    No, because:

    0) If you're anywhere "inside" the universe, all you'll ever see of the big bang is CMB radiation, and no amount of physical displacement will show you anything different.

    1) Habitually, when we consider the big bang, there isn't any reference point "outside the universe" from which to view the big bang, even if we developed FTL tech that somehow even made sense with respect to the laws of physics.

    2) Even if we postulate there was an "outside" from which to view, we have absolutely no way to predict (afaik) what such an environment would be like and how/if matter and energy could exist in it.

    3) Even if such an environment existed and could support such a spaceship, it's not certain that our FTL drive (which is just speculative fiction) would get us there. Assuming the universe is finite, the curvature of space would normally cause us to end up back where we started if we just flew off in some direction.

    Check out some of the Cosmology FAQ for clearer explanations of what the Big Bang model actually says, and doesn't say! :)
  4. Mar 13, 2012 #3


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    There is nothing to see. You physically cannot "see" the big bang. The density of the universe was so great up until the CMB was emitted that it is impossible to see past that point in time. All EM radiation emitted prior to that point was nearly immediately absorbed by the hot dense particles in the universe.
    This explanation avoids the more fundamental question of "Was the Big Bang an actual event, or just an artifact of an incomplete model?"
  5. Mar 13, 2012 #4

    No, and you are thinking about the big bang in the wrong way - as some kind of "bomb" going off in space and hurling matter outward.

    The big bang was really when the universe (the space making it up; not the matter within it) began expanding by a very large factor, anywhere from 1030 to 10100. This lasted for a very, very short time (somwhere around 10-30 seconds, I believe.) and "flattened out" any wrinkles in space.

    Unfortunately the term "big bang" creates many misconceptions.
  6. Mar 13, 2012 #5


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    I believe you are referring to "inflation", which is different from the Big Bang.
    To the OP, note that the "Big Bang Theory" is a well accepted theory that states that the Universe expanded from a hot dense state to a less dense, cooler one over time. Per wikipedia's article on it: There is little evidence regarding the absolute earliest instant of the expansion. Thus, the Big Bang theory cannot and does not provide any explanation for such an initial condition; rather, it describes and explains the general evolution of the universe going forward from that point on.
  7. Mar 15, 2012 #6


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    We do not actually 'see' the big bang, rather an event called the surface of last scattering, or CMB - which occured about 400,000 years after the BB. It will remain detectable for many billions of years. At some point in the very distant future it will become indistinguishable from stellar background radiation.
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