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Modular Physics: Largest Number in the Universe

  1. Jan 3, 2012 #1
    Hi all, I was watching a documentary (this) and a few of the people said they didn't believe in infinity. I'm fine with that but one said some physicists believe there is a maximum number then it goes back round to 0. Is this actually a theory? If so is it popular?
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  3. Jan 3, 2012 #2


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    It is important to distinguish between mathematics and physics. Infinity is a mathematical concept (which is perfectly valid).

    When talking about the universe (physics) there may be a different story. For example, most theories of the universe have the universe as bounded. This means, if you were able to travel in the same direction long enough, you could end up back where you started.
  4. Jan 3, 2012 #3
    Aren't we at a point where we're pretty sure that the universe is flat (ie. unbounded), rather than closed (bounded)? While it's true that things like String Theory predict small, bounded dimensions, it's very unlikely that the big 4 (space and time) are modular.

    In terms of mathematics, then as mathman says, numbers go forever unless you specify them.
  5. Jan 3, 2012 #4


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    We know that the universe is very close to flat or exactly flat. It could still be curved. Ever more accurate measurements keep bringing us closer.
  6. Jan 3, 2012 #5
    nope...on all counts....quit the opposite in fact....you can find lots of discussions in these
    forums on the nature of dimensions...spacetime,,,,,there are even perr reviewed papers that suggest there is no different between discrete and continuous time...they are two sides of the same coin.....just like apprpriate digital sampling can completely reproduce an analog information signal...like a TV program for example...

    also see here regarding the shape of the universe....

    and the surrounding sections like: "In a flat universe, all of the local curvature and local geometry is flat. It is generally assumed that it is described by a Euclidean space, although there are some spatial geometries that are flat and bounded in one or more directions (like the surface of a cylinder, for example)...."
  7. Jan 3, 2012 #6
    How so? After the Big Bang the whole Universe should have been expanding to all directions at the same rate so it would have a spherical shape.
  8. Jan 3, 2012 #7


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    That is not what is meant by "flat" and "curved". See here: http://en.wikipedia.org/wiki/Shape_of_the_universe
  9. Jan 4, 2012 #8
    Ok, I see the distinction. Thanks, the shape stuff is interesting, kinda like in Conway's Game of Life when you choose between border rules/no borders(modular)/infinite.

    "Science is the belief in the ignorance of experts." - Richard Feynman.
  10. Jan 4, 2012 #9


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    Let's not derail this thread into what it isn't. If you wish to discuss the "shape" of the universe, please do so in the Astrophysics/Cosmology forum.

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