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The infinite possobilities presented by the infinite amount of probabilities

  1. Oct 13, 2010 #1
    Alright now I have been tossing around this idea in my head for years now and its still quite difficult to portray my thoughts into writing but try to bear with me this is a confusing concept. Now lets just right of the bat talk about the universe haveing a infinite volume per say if you were to go one direction for the furthest distance imaginable you would still not find the end because there would yet be more ahead of you so the universe must be infinite which is just the tip of the iceberg just clearing that now. The other idea I have connected to that now is if the universe itself is infinite that its mass cannot be defined can it? Therefor its mass must also be infinite. Am I right? Now for the mind boggling part that will take awhile to be able to picture mentally which I simply want feedback on since I have never had somone to converse this situation with. Now if the universe is infinite and has a infinite mass then would it not aswell have then a infinite amount of possobilitys because of the infinite amount of probabilitys? There for to veiw this initially I tried to veiw it as its simplest form ; us, me , and right now. I did this simply by thinking of all of the events that took place to get me here right now sitting where im sitting doing what im doing. Of corse I could never be certain exactly what had happened but I had a vauge depiction of it. Now if there is a infinite amount of possobilities is there not a possobility of the same events re occuring since the were physically possible to occur in the first place? Which takes the mind into the realm of parallel universe's where this theory persay could be extended but that will only complicate things for now. So this being said and you somhow sticking along to read this entire message is there not a infinite possobility of anything that could ever occur to occur and infinite amount of times? Now is for your part I would greatly apreciate any feed back at all I have always wished to discuss this with others and please keep a open mind to this its just a idea so I thank you in advance and my apologies if this has wasted your time in any way
  2. jcsd
  3. Oct 13, 2010 #2
    I'm going to let most of the typos/grammatical errors go; but "per say" is "per se"

    This is not necessarily the case.

    I'm not sure if that is necessarily the case, but okay, lets say it is....

    I'm not entirely clear on what you're asking here. Do you mean, 'would the number of possible occurrences in the universe be infinite?' Based on the previous assumptions, yes it would---but note that this would not mean anything/everything could/would happen.

    The entire state of the universe could never be exactly the same a second time; but if you're referring to a particular incidence (like you hitting a home run a very certain way, at a certain place, etc) then there would be a certain finite probability of that happening again even if the universe wasn't infinite.

    I don't see how this has anything to do with parallel universes.

    No. Things forbidden by physical law will remain forbidden, but---given your premises---anything that could happen, would happen.
  4. Oct 13, 2010 #3
    Alright well thanks for the premier response it was much apreciated and my apologies for my failure of gramar and latin skills its late in my neck of the woods and so i fault it on tierdness.

    for your second remark how could the universe not have a infinite volume how can you see a limitation on its volume when its volume is undefined I cant imagine there simply being a point where it does not continue

    alright well we would have to say it is I am only saying it is the case because this is the only thing I can conclude in my own mind I havent read or been presented with a more logical awnser to this point in time

    what im trying to say in this quote is that if both the mass and volume of the universe were infinite which I am obviously proposing here that there would be a infinite chance for anything to occur given it was physically possible to happen along a chain of events

    Now what im saying here is that it would be possible for somthing to occur to the exact , given if it was possible to get to that point in time in the first place.. like science if it can be done can it not theoretically be done again exactly?

    this relates to parellel universes in my mind because if it can happen again for a undefined amount of times would parellel universes not exist due to it being able to occur again and again and again ongoing

    in your conclusion you say "Things forbidden by physical law will remain forbidden," and thats what im saying everything that is not forbidden must occur because there is nothing stopping it from and there are infinite possobilitys for it to occur

    and in my conclusion thanks for the response and please right back if your not completly repulsed by my reply and again my apologies for being unclear and have quite a few spelling errors along the way
  5. Oct 14, 2010 #4
    Just because we don't know its volume, doesn't mean it doesn't have a finite one. I don't know how many oxygen atoms are in this room, but there is some number of them. I have a much harder time imagining an infinite universe---given that it seems the universe has expanded from a point outward for the last ~14 Gyrs.

    If the universe is finite, that doesn't mean that you'll come to an 'edge' if you went far enough. More likely, you'd circle back to where you started (as if you were traveling on the surface of a sphere).

    It depends on what exactly you mean by "exactly." Because there is no such thing as a truly isolated system in the universe, for one thing to be 'exactly' the same as it was before---would require essentially the entire universe to be 'exactly' the same as it was. That's impossible because of the second law of thermodynamics (increase of entropy). But you're right, in that for any finite subset of objects, any finite sequence of events would be expected to occur again. (On a technical note: remember that probability can never exceed one; so in the limit that the age of the universe is infinite, the probability of any physically allowed event approaches one.)

    No, because its happen again and again in the same universe that has had a certain history. They are not parallel, they're in series.

    Absolutely. This is a popular principle (e.g. the "principle of plenitude," but it has been called many things; see for instance, http://en.wikipedia.org/wiki/Plenitude_principle) which does not require an infinite universe.

    No, you have excellent questions. The reason I read these forums is for questions and ideas just like these; they're very inspiring, and insightful.
  6. Oct 14, 2010 #5


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    Renormalization is the short answer. That is how infinities are resolved in quantum theory. It is a messy business and not proven to be mathematically sound.
  7. Oct 14, 2010 #6
    Your first point is very interesting indeed where you state "More likely, you'd circle back to where you started " It would be nice to hear you elaborate on that idea if you wouldent mind to. Another thing I find it hard to comprehend is your quote "Just because we don't know its volume, doesn't mean it doesn't have a finite one" to this I dont think its a matter of not knowing its volume its not being able to calculate it at all no matter if we were presented with all the information that could be given.

    In your second point you do note a very sound point I guess I was using the improper vocabulary when I was talking about "parellel universes" as I can see how that could be impossible to occur. I beileve what I was trying to state was more of a parellel section of the universe for instance all that we know and that effects us could it not be replicated given the universe was infinite in both mass and volume ( I understand that is still in question im only saying Given it was)

    When you say they are not parellel but in series that would have to be true but by remarking somthing to be parellel I was not stating it was parellel to our universe(section of our universe) in reletivity of where it was but in reletivity to the events that would take place in it

    I did read the link you have left and when you stated that this principle "does not require an infinite universe" but if it were to be infinite then would it not be repeating constantly an undifined amount of times?

    I thank you for your last response and hope to hear another if you have the time to do such a thing to simply clarify a few of your statments and carry on this conversation perhaps thank you again.
  8. Oct 14, 2010 #7
    ahhhhhh infinity. My favorite debate. If time is infinite there is a infinite amount of time for a infinite amount of possibilties. If mass is infinite there is a infinite amount of worlds. We seem to think of infinity as only a concept, but the truth is how can anything exist out of nothing. Maybe infinity is the only logical conclusion. The problem is that all science is useless when it comes to infinity there for it will never be accepted.
  9. Oct 14, 2010 #8
    I'm definitely not an expert on cosmology or differential geometry---and that's what you'd need to really explain this well. In essence, there are about a dozen possible (basic) geometries which could (to our knowledge) describe the shape of the universe. The main differences are open and closed, and flat or not-flat. In a closed universe (or at least some closed universes), and some types of flat universes, there aren't boundaries as in edges---but there are boundaries the constrain the overall size/volume. For instance, the universe could be like a mobius strip, which while flat, could circle back on itself. On the surface of a sphere (not-flat) you also circle back on yourself. Just imagine walking around the equator.

    It most certainty doesn't have to be this way.

    To one extent, the total universe will (so it seems) always be outside of the visible universe. The visible universe is everything within a sphere (relative to us) of radius the distance light can travel in the age of the universe. Thus the current visible-universe is about 13.7 billion light-years in radius; increasing by 1 light-year, every year. The entire universe is bigger than that; and we'll never be able to see/measure/observe/interact with anything outside of the 'visible universe.' In this way, we'll never be able to measure the size of the universe.

    On the other hand, based on people's models of inflationary cosmology (e.g. the expansion after the big-bang), some people do come up with estimates for the spatial-size of the entire universe. Which---I think---is theoretically reasonable, while incredibly uncertain.

    Gotcha, so like a parallel-region of the universe. Yeah, if the universe was infinite in size and content, you would expect that any finite region of the universe, there would exist another finite region which was arbitrarily similar to the first.

    At first I was thinking this would definitely not be the case, because entropy has to be increasing overall (a manifestation of the 'arrow of time') thus the universe as a whole would be evolving (and therefore never exactly the same).... but, if the universe was infinite, our definitions of entropy (and lots of other things) simply wouldn't apply to the universe as a whole.... so I have absolutely no idea.
  10. Oct 14, 2010 #9


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    Indeed, SciAm had an article a few years back that showed this was the case. It was eaily calculable how far away there was another Earth with another person just like yourself. It was something like 10^10^500 metres.

    This has come up more than once here on PF.
  11. Oct 14, 2010 #10

    Alright for your first comment when you stated "Just imagine walking around the equator" I understand what you are trying to say here yet this would sudjest the universe would at some point re connect where it began in a way resembling the surface a sphere. I cant see how that could simply be possible would that not be comparable to connecting a straight line to its origin?

    This second point when you remark "To one extent, the total universe will (so it seems) always be outside of the visible universe" would that not be sudgesting subtly that the universe is infinite? if its ends are unreachable that is. You also talked about the "visible universe" well with what im saying which is 100% theoretical im not looking at the visible universe but the exact oposite of that,im looking for awnsers on what I cannot see based on resonable conclusions

    Im glad my remake of what I was trying to state was understood and now it would seem the only question left to ask would be if the universe has infinite volume and mass which I do think at the moment it does which is what I would now like to discuss and hear other opinions on considering the idea or other ideas that would match it

    Yes I can understand that would be the case in this current situation but then its simply a question of the universes size so if you wouldent mind I would apreciate if you continued with your thoughts on the topic of the size of the universe


    Im not sure exactly what you are relating your comments too but when you stated "all science is useless when it comes to infinity there for it will never be accepted" I think there is place for this sort of a idea along side with science because all science really is, is what we can tell based on resonable evidence which is what im going on right now


    I would be very interested in reading such an article so if you have a link to it I would very much apreciate it. Aswell I am sure it has in the past but if you could not tell from my posts I am very new to the forums I would apreciate to re-visit the idea.

    As a conclusion I would also like to say thank you for all the comments and I would very much be interested to see everyones responses to the subject. Thanks in advance.
  12. Oct 14, 2010 #11
    Yes, that's correct.

    Not at all. It just means that the speed of light is not infinite. And the universe seems to expand faster than that. So, we are able to observe only that part of the universe which seems to be not in such hurry to get away from us.
  13. Oct 14, 2010 #12
    So you agree with me its not possible correct?

    "Not at all. It just means that the speed of light is not infinite. And the universe seems to expand faster than that. So, we are able to observe only that part of the universe which seems to be not in such hurry to get away from us." This makes sense I must have been confused by the visible universe and the reachable universe a simple error on my part my apologies.

    Aswell thanks for your contribution
  14. Oct 14, 2010 #13
    No, I agree with your explanation. The straight lines are closed lines with finite length.
  15. Oct 14, 2010 #14

    Im not sure quite exactly what your trying to say could you please elaborate more

    thanks in advance
  16. Oct 14, 2010 #15
    Just that what you see as straight line is not necessary straight line in some higher dimension. Straight lines on the surface(2D) of a sphere are circles in 3D (our space). If you walk on the sphere in a straight line, you would be circling around the sphere. So if you mark your stating point you will eventually come back to it. If you are not aware there is 3rd dimension it may sound strange. The same is possible for our space. It can be curved in any higher dimensional space.
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