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B The edge of the universe

  1. Feb 26, 2017 #1
    Hypothetically, what does the edge of the universe look like?

    Past our known visible universe to the edge of the expanding universe what is it like?
  2. jcsd
  3. Feb 26, 2017 #2

    Simon Bridge

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    As far as we can tell there isn't one... at least, no reason to think there may be an edge way way out there the way you seem to be thinking.

    The current simplest best model for the overall topology of the Universe is "flat, infinite".
    It may be that the Universe is closed in the sense that hypothetical travellers could keep going in one direction and eventually and up where they started.
    The simplest non-infinite Universe that fits the data would be Toroidal.
  4. Mar 1, 2017 #3


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    You are effectively asking 'what is beyond all that is known'. A shaman would roll his eyes and simply respond 'the unknown'. A scientist would shrug and say 'nothing'. While that sounds pretty vacuous, it captures the essence of the question. You cannot picture the universe from outside the universe because everywhere and anywhere possible to go is, by definition, part of this universe. The only known constraint is called the particle horizon - the distance photons have traveled since the beginning of time and that 'boundary' continues to recede from us at light speed. Distance, however, is always relative to something and that something is the big bang: which turns out to be singularly unhelpful. The big bang occurred everywhere - not at some uniquely identifiable location.
  5. Mar 1, 2017 #4


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    @Lewis123 I recommend the link in my signature
  6. Mar 1, 2017 #5
    You are asking what exists outside of everything that exists.
  7. Mar 1, 2017 #6


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