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Do infinite probabilities hurt multiverse theories?

  1. Aug 7, 2010 #1
    Do "infinite probabilities" hurt multiverse theories?

    I got some good responses to my last thread on here I thought I'd try one more.

    I'm wondering about the multiverse theories where whenever a quantum 'decision' is made, the universe branches out into versions of itself in which each of the possibilities actually occurred. I understand this idea springs from a very literal, minimalist interpretation of shrodingers wave equation, which says nothing about the 'colllapse' that leads to a specific outcome.

    Now here's my question. Is the idea that, "if every possible result occurs, then the whole notion of probabilities is destroyed," do serious damage to such multiverse interpretations of quantum mechanics?

    I know there is plenty of mathematical research involving the study and comparing of infinities. It seems like it would apply here. Just like the infinite set of all numbers is bigger than that of just the even ones, the infinite set of high-probability quantum outcomes, is greater than that of low-probability ones. Am I possibly confusing conceptual tools with 'real things' here though?

    I as a good analogy what happens if you consider a spaciously infinite universe. We can say right now, "brown dwarf stars are more common than red giants." To me the argument I mentioned is like saying that, "because the universe is infinite, there are just as many red as brown stars." Obviously that's not very helpful, and it makes perfect sense to control for the infinity by looking for stars per unit of space. So for any section of the universe, this proportion of stars will hold up. Can't we do something similar with the multiverse theories where we say, "within this portion of uber-space (tm:cool:) there will be this many decaying particles, out of the total," for example?

    I wouldn't be asking this if I hadn't read so many serious suggestions of what I mention.

    Thanks for your time.
  2. jcsd
  3. Aug 7, 2010 #2


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    Re: Do "infinite probabilities" hurt multiverse theories?

    You can assign probabilities to infinite sets, that's what all probability densities do. The formal mathematical justification for the coherence of this idea (as well as an explanation of why it won't work for all types of infinite sets) can be found in measure theory.
  4. Aug 7, 2010 #3
    Re: Do "infinite probabilities" hurt multiverse theories?

    I would say no.

    To talk about Multi Verse theory you must be aware of the TimeSpace phenomenom.
    TimeSpace being on the other end of the universal-spectrum where Space exist as a 1d linear thing, and Time is 3D.

    In Spacetime, the realm which we live in, there is finite everything to certain degrees. In TimeSpace, everything is infinite... energy, knowledge, existence.

    Meaning, through TimeSpace, there are infinite possibilities of universal existence. "Finite" things only exist in physical universe. In TimeSpace, physical things are infinite. It's not like physical things can actually exist 'in' TimeSpace. TimeSpace and SpaceTime coexist but at the same time they don't. It's a confusing concept.

    Since to get to other 'universes' you must go through TimeSpace(which is possible through wormholes), there are infinite possibilities of existent universes.

    The way I like to think about it is...... if you can imagine it, it is real... just not real in our physical universe. Meaning things like unicorns and leprechauns in fact do exist, just not in any way that we can currently measure or test, so for logical argument purposes you can't argue saying they exist. Saying things exist usually refers to their existence in this universe. Meaning, everything that doesn't actually exist here, has an infinite possible chance of existing in other universes. There could even be a universe where DNA is made up of fragments of pure diamond, but its would have to be the laws of that universe which allow that to occur. It's hard to try to invent something in our heads that would work on that kind of scale, because we simply can not sit down and calculate every single factor that plays in.. because then you have to fully understand the possibities of potential elementary particles and their fundamental laws of existence(which can vary universe to universe)

    People need to realize that on the TimeSpace scale, everything is infinite. Every possibility that could ever possibly occur is occurring at all times, somewhere, just not here. In TimeSpace, nothing is ever not happening and everything is always happening.

    This is why the universe can keep expanding, because there is infinite room for it to expand to, though because the universe is physical, it can never actually be existing in the infinite space, it can only continue expanding into that infinite space. Though the universe can not expand forever. Not because it will run out of space(because it wont), but because of other fluctuations in the SpaceTime fabric. I believe it's been predicted when it will implode on itself and start over, though I am not current sure of this number.
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