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Question about the multiverse and infinity

  1. May 25, 2007 #1
    I've wanted to ask this for a while since it has been confusing me for too long now... if our universe is infinite and nothing can possibly exist outside of it (other than a putative God although no one has an idea how that could be, since Kant proved quite a while ago that existence itself is entirely contingent on the spacetime continuum), then how can there be hidden 5-6-7-10-11 dimensions or an infinity of other infinite universes especially since an infinity can never be added to an infinity? Where would they reside if not in our infinite universe? This doesn't make any sense no matter how precise the math is. And so I must conclude that all the infinity of multiverses/megaverses/whatever is somehow embedded within our infinite universe and cannot exist outside of space-time (even the non-local wafefunction collapses within it together with it's "infinite minds and infinite world" scenarios). In fact, once we localize the infinity of what could/does exist courtesy of all the other infinite universes, it becomes much more easier to actually process all this without sliding into insanity.

    Also, if there is an infinite number of infinite universes/multiverses/megaverses, then doesn't that make us even smaller specks of dust compared to the speck of dust that we are right now? Or maybe our universe is a speck of dust compared to the nested infinity that houses it all ad nauseam (but how is that possible after what i've written above?) It's all mind-boggling and terribly annoying because I can't fathom it.

    And lastly, what about our birth? Do we come from nothing and suddenly become "embroiled" in this infinity of universes/multiverses/megaverses? That's the hardest part because I don't understand where does consciousness comes from (and I won't even go into the "why" category of questions lol)
     
    Last edited: May 25, 2007
  2. jcsd
  3. May 25, 2007 #2
    you are simply hung up on semantics- the Universe IS all that exists- but there is almost certainly much much more to the universe than we see- the Universe isn't merely the space-time we observe- but also by definition includes all parallel histories and cosmic regions in all 'dimensions'

    it is just that recently due to Multiverse ideas many have taken to use the term universe as simply another hierarchical cosmic structure- but it is still also used in other places to describe all that exists-

    as for your last question I would say the concerns about causal origins are moot when considering Time as not absolute- for any world with n spatial dimensions- every possible state of every possible history of that world can be embedded in a timeless static structure of n+1 spatial dimensions- or if a cosmic region is causally bounded [such as our Hubble volume] but embedded within a transfinite/infinite space there would be infinite such bounded regions which would statistically contain every possible state that such a region can have- these ideas lead to the concept of 'block time' - the universe need not have origins in a 'past'- as the past is merely a special case of parallel worlds that correspond to the most likely physical states in your world's causal history- the universe simply exists- what we call time and histories can be an ensemble of static sets of states if the ensemble is infinite [or at least contains more world-states than the number of possible configurations they can have]
     
    Last edited: May 25, 2007
  4. May 25, 2007 #3
    So everyone is hung up on semantics then?

    But conscious entities such as us do need origin in the past...
     
  5. May 25, 2007 #4
    ayep- there have been other threads here about the different definitions of 'universe' and how they cause confusion when multiverse ideas are discussed- I would suggest reading Max Tegmark's recent paper: http://arxiv.org/abs/0704.0646


    a 'conscious entity' is merely a set of physical states which happen to correspond to structures of matter with the properties that they process information from the surrounding environment with feedback/storage/etc- an infinite set of possible states would by definition contain the states of every possible such conscious entity that could exist in every possible universe at every moment in every possible history- therefore every possible history that such a conscious entity can observe would lie in the ensemble without Time/motion- but the entity would perceive time and motion as a result of the causal relationships of the states in it's observed history- because a conscious entity's structure is very complex and determined by very specific causal factors- the 'past' seems very specific and very absolute to such an entity


    the reason why the Universe and conscious entities appear to have an origin point is because simple rule systems with very simple eigenstates are far more probabilistically numerable statistically in an ensemble of all possible structures than complex random/eternal/etc systems- Seth Lloyd has described this with the Monkey's on typewriter's composing hamlet metaphor- the argument is that complex worlds are very unlikely to result from monkey typing randomly on typewriters- but monkeys on laptops could produce complex evolving universes from just a few random keystrokes because there are innumerable short algorithms that could easily be randomly input that when run produce complex states- so the thinking goes that probability determines that the most likely causal history of an observer will be from a simple algorithm evolving into a complex world- and such an observer should see a simple eigenstate in a finite past- such as the Big Bang
     
    Last edited: May 25, 2007
  6. May 25, 2007 #5
    You want ot say that the entire past, present and future history of the human race is already written in advance in some form of an "omega point"?
     
  7. May 25, 2007 #6
    this is not as controversial as it seems- in fact this is essentially what Einstein tried to express with 4D space-TIME- Einstein argued it was more natural to express a 4D structure that simply exists rather than a 3D structure where events occur in 'time'


    Suppose that our universe is indeed some form of computation.
    A common misconception in the universe simulation
    literature is that our physical notion of a one dimensional
    time must then necessarily be equated with
    the step-by-step one-dimensional flow of the computation
    ...computations do not need to evolve the universe, but
    merely describe it (defining all its relations).
    The temptation to equate time steps with computational
    steps is understandable, given that both form a
    one-dimensional sequence where (at least for the nonquantum
    case) the next step is determined by the current
    state. However, this temptation stems from an outdated
    classical description of physics: there is generically no
    natural and well-defined global time variable in general
    relativity, and even less so in quantum gravity where time
    emerges as an approximate semiclassical property of certain
    “clock” subsystems . Indeed, linking frog
    perspective time with computer time is unwarranted even
    within the context of classical physics. The rate of time
    flow perceived by an observer in the simulated universe
    is completely independent of the rate at which a computer
    runs the simulation ... Moreover, as emphasized by Einstein, it is
    arguably more natural to view our universe not from the
    frog perspective as a 3-dimensional space where things
    happen, but from the bird perspective as a 4-dimensional
    spacetime that merely is. There should therefore be no
    need for the computer to compute anything at all — it
    could simply store all the 4-dimensional data, i.e., encode
    all properties of the mathematical structure that is our
    universe. Individual time slices could then be read out
    sequentially if desired, and the “simulated” world should
    still feel as real to its inhabitants as in the case where
    only 3-dimensional data is stored and evolved

    Max Tegmark
     
    Last edited: May 25, 2007
  8. May 25, 2007 #7
    Alright, that makes sense. But how do the future conscious entities actually come to be and where are they at the moment or they are merely a possibility encoded inside the fourth dimension?
     
  9. May 26, 2007 #8

    Chronos

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    A different approach might be helpful. Where did you come from, nothing, or a precursor potential? The trail winds back upon its tail. There is no deterministic reason for you to exist, yet you do. It is very puzzling. The same might be said of the universe. I can't explain it, but pleased it happened to work out that way.
     
  10. May 28, 2007 #9
    Well, I'm happy too that it worked out that way ;)
    But, although it's tempting to proclaim because it seems to us that we existed forever and will never die (a particular property of consciousness) that the birth of the universe is similar to our birth, we know that we weren't really present during the big bang :)

    You think the time before the big bang (which is an oxymoron really because time began at the BB) was the same for our, as you said, individual "precursor potential"?
     
    Last edited: May 28, 2007
  11. Jun 6, 2007 #10
    fact you are conscious of a universe- theory, a universe exists for you to be conscious about it... this theory need not be the case (^_^)
     
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