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Does an infinite universe effect an infinite outlook?

  1. Apr 5, 2004 #1
    Is our observation necessarily limited in an infinite physical universe?
  2. jcsd
  3. Apr 5, 2004 #2


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    The current thoughts that I have about the universe is that it is impossible to be finite. I'm not talking about matter incapable of pulling it back together, or anything that is up in the air right now. When I'm done with it, hopefully within the next year, I'll post up my conclusion or hypothesis whether it is correct or wrong.
  4. Apr 5, 2004 #3
    Observation of what? Or Observation of everything?
  5. Apr 12, 2004 #4


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    The most obvious answer would be 'yes', because c is constant (and much less than infinite), and all causal connections - including 'observation' - happen at c or slower.

    But perhaps Loren has some particular slant, not yet shared, for our consideration?
  6. Apr 12, 2004 #5
    An infinite physical universe, having infinite time, would allow the observation (by an immortal observer) of its infinite space even with a finite light speed. Which introduces the question: can an observer possess properties (e. g., life-time) of unlimited values?
  7. Apr 12, 2004 #6
    YOu cant see all the universe even in an infinite amount of time because space itself is expanding. The frontier between the things that will be visible and the things that wont is called the event horizon, and is actually at approximately 17 billions of ly of distance
  8. Apr 12, 2004 #7


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    I think we'll rapidly need to sharpen the meanings of the terms we're using here ... e.g. 'infinite physical universe', 'infinite time' ... both in themselves and wrt the universe we appear to current live in ... :biggrin:
  9. Apr 12, 2004 #8
    This seems a lot like complex infinity, is it not? I think then, it would depend on the outlook of what infinity actually is and what its physical characteristics hone to each unknown quantity. If it would be a continuum of space, who knows? As Nereid said definition in terms need to be defined here for criticism and encouragement, but don't ask me, I'm only in 10th grade! :biggrin:
  10. Apr 12, 2004 #9
    Frank Tipler's "Physics Of Immortality"

    An oldie, but a goodie.
    Frank Tipler's "Physics Of Immortality" is a great read, and touches on the "intangible and indefinable values" of "infinity" and "immortality". The Maths may be a bit much for most, but I think its perhaps the most daring and revealing work out there, touching on this theme.
    Check it out...
  11. Apr 12, 2004 #10
    Nereid et al,

    Let me restrict an "infinite universe" to all possible topologies of our observable spacetime manifold, where "infinite time" or "infinite space" correspond to geodesics integrated over those topologies between observer and object.
  12. Apr 28, 2004 #11
    If the universe is infinite, how can it be expanding.

    Space is infinite. The universe is finite.
  13. Apr 28, 2004 #12
    How then can infinite space be expanding?

    Infinity is a concept approached in limits, not a number. An "infinite" (velocity) field in space may be assigned an infinity of values, even those approaching infinite velocity.

    Please return to my last post which defines further the thread question: "Is our observation necessarily limited in an infinite physical universe?"
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