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< Infinity >

  1. Jul 10, 2003 #1
    In many articles I have found that : Universe is (in time & space) infinite.................................

    But I don't understand what is the law or formula behind this ???

    Can anybody explain it further ???
  2. jcsd
  3. Jul 10, 2003 #2
    That's just the thing, there is really no formula behind whether or not the universe is infinite... It's all simply speculation. However, there are many modern cosmological readings that strongly suggest the universe is infinite because it so well satisfies certain theories...
  4. Jul 11, 2003 #3
    it isent infinte as i under stand it it is constanly exspanding so

    hey how do they even know that infitey exist have they ever counted to it?
  5. Jul 11, 2003 #4
    Yes! I wanted to know how they are so sure about it's infinitiness ???
  6. Jul 11, 2003 #5
    The question is how can it NOT be infinite?
  7. Jul 11, 2003 #6
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  8. Jul 11, 2003 #7
    Last edited by a moderator: Apr 20, 2017
  9. Jul 12, 2003 #8
    If I assume you have read it then you should ralize that it is not a concept that anyone can think of, hence a formula for infinity is impossible.

    The only thing that is left, by that posting I made, is admittance to Belief, you either belive in an infinity, or you don't, but it cannot be proven out, not one way, nor the other.

    Hows that?
  10. Jul 12, 2003 #9
    So you are saying that because we can't calculate to infinity then it cannot exist? Do you consider that a proof?

    I find thinking of infinity quite easy. I just can't fit it completely inside my mind, but so what? There are MANY complex phenomena that I cannot imagine in their entirety.

    Ok, but it requires an extra assumption that space suddenly stops and is therefore finite.

    Needs a bit of work.
  11. Jul 12, 2003 #10


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    It doesn't require a sudden stop to be finite.
  12. Jul 12, 2003 #11
    oh yeah the curved space thing... another hyper-pathetical
  13. Jul 13, 2003 #12
    Well apparently you are willing to decieve yourself, as if it is NOT a thought, then no one can 'think' of it, partially or in it's entirey.

    No delineations, NO boundaries, NO edges, No appearance of space, NO visuals, ergo, No Conceptualization available.
  14. Jul 13, 2003 #13

    You can think of it logically. Infinity simply has no edges or boundaries.

    non sequiter

    Just because a substance has no ultimate boundaries does not mean it has no internal structure.
  15. Jul 13, 2003 #14
    As I stated, just because you are willing to decieve yourself, doesn't mean you got it right.

    Al thoughts are bounded, ergo you cannot have an unbounded thought, but you can fool yourself into thinkng that you have had one.
  16. Jul 13, 2003 #15

    Just because you can state that I am decieving my self does not mean that I actually am.

    Care to explain how you wash the hog?

    I never said that I could have an unbounded thought. The mind is certainly finite. That is why the imagination is useless to understand infinity. Infinity must be understood through logic not imagination.

    If I say Infinity has no boundaries, I have said a true statement about infinity. Do you suppose that this statement must be infinite?

    To understand something you need not replicate it in your mind. The mind is capable of generalization and abstraction.
  17. Jul 13, 2003 #16


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    I am with subtillioN that you can certainly think logically about infinity...

    but I'm at odds with his definition; infinity is typically used in contexts where we may (at least sometimes) ascribe quantities to entities in question, such as sizes of sets, lengths, or volumes. We use infinte/infinity when either we have "transfinite" numbers which are larger than any real number (such as the case of sizes of sets), or when there is no upper bound to the quantities in question (such as distances in the euclidean plane)

    subtillioN is thinking in a context where "no edges or boundries" is a sufficient condition for there to be no upper bound on distances or volumes, but that is not in general a sufficient condition.
  18. Jul 13, 2003 #17
    In mathematics there can be infinities of different magnitude. That is because they are dealing with the indefinite division of continuity.

    I do not consider this to be infinity proper, but the transfinite.

    True infinity can have no magnitude.
  19. Jul 13, 2003 #18
    It becomes the paradox of presentation of the universe, inasmuch as you can count things in the first place, because, if you were truly observing, or thinking, of the infinite, you would have nothing in your head, absolutely nothing, ergo not even the beginning of counting anything!

    Think of it in the sense of looking at the surface of a perfectly lit/illuminated sphere all at once, the entire surface, observant thinkers will realize that visually you can see nothing because unless the surface of the sphere is lit in an asymetrical manner, all you will "see" is 'flat space' with nothing to distinguish anything from anything else.

    Infinite is NOT a concept in your head, it cannot be, because, your imagination is limited, as well as is your thinking ability. (other then the typicono'graphic that is the word itself)

    To be human is to experiance these limitations.

    That you seem to wish to refuse to accept them, little I can do about that one.

    In an infinite system you cannot even begin to count, as there is not one thing that is distinguished. (Neither beginning, nor end)

    (Yes, I know, sounds contradictory, but in the complete understanding of the universes construction it ends up making sense......go Figure!)
  20. Jul 13, 2003 #19

    First of all you make the error of equating observation with thought. I am talking logic not observation or imagination. This distinction is critical.

    I am not talking about homogeneity whatsoever. Infinity is not equivalent to homogeneity.

    Of course the infinite cannot be contained in the finite mind and the infinite is not a thought. This does not mean that logic can not define the infinite without encapsulating it.

    You have simply misunderstood them.

    Again you are confusing infinity with homogeneity.

    "Everyone regards the question of the infinite as most difficult, if not insoluble, through not making a distinction between that which must be infinite from its very nature, or in virtue of its definition, and that which has no limits, not in virtue of its essence, but in virtue of its cause; and also through not distinguishing between that which is called infinite, because it has no limits, and that, of which the parts cannot be equalled or expressed by any number, though the greatest and least magnitude of the whole may be known; and, lastly, through not distinguishing between that, which can be understood but not imagined, and that which can also be imagined. If these distinctions, I repeat, had been attended to, inquirers would not have been overwhelmed with such a vast crowd of difficulties. They would then clearly have understood, what kind of infinite is indivisible and possesses no parts; and what kind, on the other hand, may be divided without involving a contradiction in terms. They would further have understood, what kind, of infinite may, without solecism, be conceived greater than another infinite, and what kind cannot be so conceived. All this will plainly appear from what I am about to say."

  21. Jul 13, 2003 #20


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    The great thing about human thought is that we can think about what we can think. Recursive logical structures are exceedingly powerful...

    At "first order", you may be right and we cannot conceptualize infinity at all.

    However, at "second order" we can talk about first order thought itself. We can talk about things that fail to be conceptualized at the first order level and analyze how and why we can't conceptulaize it at that level, allowing us to synthesize second order concepts.

    In particular, I can think about infinity without having to simultaneously think about everything "in" that infinity.

    That addresses your argumentation, but I think you're thinking about infinity in entirely the wrong way. Most of these arguments that we cannot conceptualize infinity, et cetera, et cetera, are highly dogmatic; if you refuse to step boldly forward and try to figure out what you mean by "infinity", then, by golly, you will not be able to talk logically about it!

    On the other hand, mathematicians do step boldly forward. We distill the "essential elements" out of peoples' vague ideas about infinity until we get a nice, precise definition appropriate to the context, and we get a lot of useful mathematics out of it.
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