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A super dumb question

  1. Jun 1, 2005 #1
    Somebody say if you are not there, you don't understand what's happending there.
    Is that the same reason that we can't explain why this universe is unlimited just because we can NOT get to the limit of the universe if it does exist.
    Anyway, I can't understand something is unlimited, just like a natural number can grow up forever.
  2. jcsd
  3. Jun 1, 2005 #2


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    As I've said before, there's no such thing as a dumb question if you're really seeking an answer. In this case, I don't think that the human brain is capable of comprehending something like that as a physical structure. Mathematics is the only way to get a handle on it. You can build all of the hypercube models you want to, and still not be able to 'see' the time dimension. Same for a finite, yet unbounded, entity such as the universe. There are too many dimensions to be dealt with by a brain that can only detect 4 of them and see 3.
  4. Jun 1, 2005 #3


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    Do you also have the same problem with linear algebra and infinite series expansion?

  5. Jun 1, 2005 #4


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    That's basically correct. Current physics suggests that the finite speed of light limits what we can say about the universe. That's why we have to make the distinction between an "observable universe" and the entire thing (there are a variety of terms in use).

    Practically speaking, I think theorists tend to have the same discomfort with infinities. They make for a nice mathematical tool, but we get worried whenever they seem to show up in real life.
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