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Finite space in infinite time

  1. May 8, 2003 #1
    Lectori salutem.

    Can anyone refute the finite space/energy/matter in infinite time theory?

    Finite space/energy/matter implies that the universe is not something endlessly extended, but set in a definite space as a definite force.

    Infinite time implies that it will never reach a final state of equilibrium.

    This means that the universe consist of a finite amount of energy (in whatever manifestation) that flows on in an infinite stream - not infinitely deep or wide, but infinitely long.

    I will welcome any serious thoughts on the subject.

    Thanks in advance!

  2. jcsd
  3. May 8, 2003 #2
    From what perspective, reason, or observation, you conjecture that space is finite in extend.

    All we know or assume is that space has no edges or boundaries. Which does not imply it being infinite, but neither disables that option.

    I realy doubt that space or matter are finite in extend, in more or less the same way as I doubt that time is finite in extend.

    If space would be finite in extend, and have no boundaries or edges, this means that space is not flat, but curved. If space is sufficiently large, we might not observe that fact on small distance scales.

    Current astronomical observations indicate however that space seems perfectly flat. It is not a proof, but just an indication that space can be infinitely large. And if not, it would need to be very large indeed. Most atronomers assume that we only see a small fraction of all of space.

    Infinite space is a real candidate, and not just a theoretical model for the universe.
  4. May 8, 2003 #3
    All I need is the POSSIBILITY of finite space; and that possibility exists until it is refuted - i.e. until the infinite-space theory is proven PRACTICE.
  5. May 8, 2003 #4
    Why do you 'need' finite space?

    What is your motivation for assuming that space is finite in extend?
  6. May 8, 2003 #5
    If space were infinite it could not expand. This is contrary to the big-bang theory.

    Simply put, if the universe is a finite force in infinite time, this means that all possible conditions will exhaust themselves and sooner or later the same condition shall come about. From which it follows...
  7. May 8, 2003 #6
    Why do you think that? The assumption is false.

    Take for instance the infinite number set. You can add to it an infinite amount of numbers, without problem. Also you can subtract from it an infinite amount of numbers, while it sill maintains being infinite.

    You have to look at space expansion as an expansion of the metrics.
    An infinite space that expands still remains infinite.

    However, it can be stated that the Big Bang is the expansion of an initial region as small as a infinitesimal small part of the size of a proton. However, in the embedding theory of inflation, this is just one region, and the surrounding space is still infinite space.
    Inflation indeed talks about a small region of space that expands, which means that that region, no matter how large and how fast it expands, always will be finite in size.

    That everything would repeat itself? every moment is an eternal moment? well it explains my feelings of deja-vue..... LOL

    The situation is however not very different in an infinite space, cause then it could be said that there must be infinite many planets exactly like earth, with the same inhabitants, etc.
    Last edited: May 8, 2003
  8. May 9, 2003 #7
    And what would this finite existence be residing within? Nothing? Impossible.
    Which implies that all things within the universe have always been effects. No cause. That doesn't make sense either.
  9. May 9, 2003 #8
    Re: Re: Finite space in infinite time

    The model of a 2D sphere curved in 3D space, is a good model for a finite, yet unbounded space. For 3D space it must mean it is curved in 4D space. But all astronomical observations conclude that space is almost perfectly flat. From observation we thus concldue that space is indeed very large, possibly infinite.

    Not realy. All effects are at the same time causes for the next effect. Which doesn't mean that I conclude that a circular chain of cause-and-effect, based on the finitiness of space, makes any sense to me...
  10. May 9, 2003 #9
    Re: Re: Re: Finite space in infinite time

    Sure. But what is this "model" residing within? Certainly not 'nothing'. That's a logical impossibility.
    Something must have boundless existence. This is clear. But this thing cannot reside within 'nothing'. Therefore, existence itself is not finite.
    But infinite-existence imposes singularity upon existence itself. The position of any thing within such an existence is thus subjective.
    No effect can lay-claim to being the true cause of any event.
    To say that I (lifegazer) am the absolute-cause of this post, for example, is utterly incorrect.
  11. May 9, 2003 #10
    Re: Re: Re: Re: Finite space in infinite time

    While I agree on the conclusion that space is infinite, this does not mean that your argument against finite space is correct. What is against a 3D sphere curved onto itself as a 4D hypersphere? (except that it implies that time had a beginning)

    We come here again on the point which you argued against, namely that the chain of cause-and-effect is infinite indeed, that means: it has neither a begin nor an end. A finite circular cause-and-effect chain has neither a begin or end, but this means that everything happened already an infinite number of times.
    (hmmmm. it appear to me I already say that many times before? lol)

    BTW: Did you change your mind on the beginning-of-time thing?
    Last edited: May 9, 2003
  12. May 9, 2003 #11
    That is a mathematical abstraction. "An infinite space that expands" is an oxymoron: it implies that the space have bounds which expand. However, the word infinite means "without bounds"...

    That is very interesting. Thank you for submitting your views.

  13. May 9, 2003 #12
    That is a incorrect view. Model all of space as a flat sheet, infinite in extend, and draw a grid on that sheet.
    The expansion of that infinite sheet can now be visualized as a change in the metrics of that grid. It gets larger.
    And the only way we can know about that, is because the objects on the grid (the atoms, and material objects) do not expand themselves.

    In fact this situation is similar to the grid not expanding, and all material things on the grid, contracting.
    However, I never heard a physical explenation to that, although it must be the same thing, we only changed the definition of our length unit..... Physical laws are absolute the same and not dependend on our choise of the lenght units....

    Can anyone explain me this, cause this aspect of "space expansion" I still don't get?

    The fact that either time and/or space is infinite, seems both lead to many contradictionary implications. Either "this moment" happened an infinite number of times already, or "this moment" happens at infinitely many places at once....
  14. May 9, 2003 #13
    Re: Re: Re: Re: Re: Finite space in infinite time

    I said that existence was infinite. Not space.
    ... and why do you disagree with my argument about finite-existence?
    Yep. A stumbling-block of communication, is this.
    My position remains unaltered. If all effects are the product of causality, and causality is infinite in regress, then there cannot be a 'product'. Nothing you have posted has ever convinced me otherwise. Sorry.
  15. May 9, 2003 #14
    Re: Re: Finite space in infinite time

    Nothingness, ye-e-es. But the idea of something within nothing is a rational impossibility: for, to envision this, one should be able to imagine "The Nothing"... Utter darkness? But that is still something. No, "space enclosed by nothingness" means there is only space, not within something but in itself.

    It is indeed a vicious circle. But is a circular argument neccesarily a false argument? Or must you really infer a "Creator" as a primary cause. Who, then, invented the Creator? Did He invent Himself? Or has He always been there? - But this is merely a repetition of the question...
  16. May 9, 2003 #15
    Or Both?
  17. May 9, 2003 #16
    Absolute-nothing is utter nothingness. Not utter colour or colourlessness or any other thing which you'd care to mention.
    You cannot have something residing within such a state. It's rationally impossible.
    Then it is not 'nothing', is it? And if you want to put 'something' beyond universal-existence, you just extend existence beyond our material-domain. Hence, existence is boundless and non-finite.
    Sorry, but this is no longer a rational discussion. You cannot have a finite-entity residing within nothing other than itself. The very-fact that the entity is finite means that it must be embraced by another entity - which cannot be 'nothing'.
    Not if the circular argument makes sense.
    Personally, I think so. Most here will side with you though.
    Existence itself is eternal (note: by existence, I do not automatically infer that the material-universe is eternal). This is obviously-apparent when one realises that something cannot emanate from absolute-nothingness. And since something does exist now (whatever that thing may be), then we can be sure that this thing has always existed, and always shall - since 'nothingness' cannot come of something.
    Thus, existence is eternal, and the question about its own causality is shown to be meaningless.

    Like other members here, you seem to want to use the term 'nothing' so that it actually is 'something'. This is your base-error, imo.
    By the way, welcome to the forums.
  18. May 9, 2003 #17
    I made the mistake of assuming you could fill in the blanks I intentionally left in this part of my argument. You have, but at the cost of thinking that I could not do so myself. Then you gave the same impression to other readers by cutting my argument into pieces.

    This conclusion does not follow from the premises. It rather seems to be some kind of idée-fixe you have.

    These are all personal opinions, not facts. Why must something be enveloped by something else?

    When asked whether you think there is a Creator, you said: "Personally, I think so." That is not very scientific. What makes you think there is one?

    This has been my point from the beginning - with the incorporated notion that the essence of existence is to all eternity flux.

    Thank you for making me feel at home.

  19. May 9, 2003 #18
    One can never model all of space if it is infinite...!
  20. May 9, 2003 #19
    Re: Re: Re: Re: Re: Re: Finite space in infinite time

    Your reasoning is obviously wrong. Because your reasoning assumes at a certain point there is a begin to the infinite chain of cause-and-effect. From there on you reason that if such a begin is an infinite time from the present, you cannot get from there to the present, and hence there can not be a product.
    We been on this point now many times, and the error in your argument is that you put in the conclusion of your argument (time must have a beginning) in the premise to your argument.
    Infinity, namely, implies there is no begin to the time line. So, wherever you place your 'begin point' where you start your count, you always leave behind you an infinite amount of time.

    So, your reasoning is circular. Your basic (implicit) assumption is that time had a begin. Then you state that if time is infinite, that an infinite amount of time must have been passed since that beginning. You then conclude: that is impossible, so time could not be infinite, hence time must have had a beginning. But that was just the start of your reasoning, the premise you implicitly smuggled into the argument!

    Your error: you have assumed that there was a begin (else, where do you start counting?), while in fact, infinity of time in both directions (past and future) means that there is no begin or end to time at either side of the timeline.

    Please reread that part of the argument in the text of Friedrich Engels in the thread: https://www.physicsforums.com/showthread.php?s=&threadid=958".

    The fact is, your conclusion is wrong, cause the 'product' (the here and now) exist (that is for sure). Further we now that all things of the present must be the effects of previous causes, which themselves are also effects of previous causes. Hence it follows that time had no beginning. Otherwise, there would have been effects without causes.
    Last edited by a moderator: Apr 20, 2017
  21. May 9, 2003 #20
    You are very excellent in this reasoning. And for most part the reasoning is correct, except for the fact that you rob the material basis from existence. What can exist if no matter in whatever form (mass, energy, fields, whatever there is that can move/change in time and space) would exist?
  22. May 9, 2003 #21


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    Actually, the reasoning is crap. The claim that a finite manifold must be embedded in external space has been repeated often, but is not founded on logic or any reasoning at all. But maybe you missed that part.
  23. May 9, 2003 #22
    I already pointed that out. The 2D anology of space, modelled as the surface of a sphere, which is of course a finite size, but has no boundaries or edges; mathematically that is perfectly possible, and does not need 'outside' space.

    Nevertheless, from observation and theory, I do not think that real space is finite.
  24. May 9, 2003 #23

    Tom Mattson

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    Don't worry: He doesn't give that impression to any of the regular readers.

    Ugh--Please, let's not. This was a big enough mess the first time. You can read about it here, if you are so inclined:
  25. May 9, 2003 #24


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    Edges aren't even the problem. The claim that finite space must be embedded in something external is where the argument falls apart. Even if some models of the expanding universe found by Georges Lemaître (with a center and edge) were correct, the claim is still wrong.

    But I guess intuition takes priority over reason with some.
  26. May 9, 2003 #25
    Apart from the false argument against a finite extend of space, do you realy think that space is finite, and for what reason?

    To state that space is infinite is somehow difficult, because that aspect of space can not be observed directly. The only observational point is the "flatness" of space. But since we can not distinguish between an exactly flat space and space that is very near to flat (meaining: space is very big), how can we find out wether or not space is infinite?
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