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Multiverse just passes the buck on

  1. Feb 7, 2005 #1
    Multiverse just passes the buck on....

    The idea of a Multiverse just passes the buck on to another order of magnitude of a cosmic scale. If we are simply one Universe of infinite Universes in a larger Multiverse, then why can't there be a 'Megaverse' that contains infinite 'Multiverses'?

    In addition, if it is true that we are one Universe and there are infinite parallel Universes a few problems arise:

    1) What is the smallest difference between adjacent Universes that still makes them distinctly separate? For example, say there is a Universe beside ours that has played out precisely as ours has for 13.7 billion years, but in 2 minutes time from now a single leaf falls off the tree outside your window that did not fall off in the other parallel Universe. Is this the point that our parallel Universe truly detaches from ours and becomes separate, or is it the point that this parallel Universe is actually becomes born and in fact it never existed up until this point because it was superimposed on ours?

    2) The question then evolves to why should a leaf falling be the smallest event that constitutes a difference between our Universe and a parallel one? Why shouldn't the bacteria on the leaf that weakened it and caused it to fall be the smallest difference defining event? Or why shouldn't the oxygen atoms the bacteria metabolized 10 minutes before attacking the leaf that gave them the strength to finally make the leaf succumb be the smallest difference defining event? Or why not the temperature of the Cosmic Microwave Background Radiation that held at 2.7 degrees Kelvin just long enough for Earth to capture the oxygen atoms from free space?
    So you see, just how small does/can a difference defining event have to be? Planck scale? or less even?

    3) What about time? Say we have two Universes that are babies (still singularities) and we know for certain that once allowed to explode, each Universe will expand and fizzle out over several billion years in exactly the same manner even to the smallest degree. Now we introduce a condition where we set one Universe off a day earlier than the other Universe. To a person watching all this happen from above in their Multiverse, its clear that no, these two Universe's are not identical because the Universe that was born earlier, has all its particles in different positions from the Universe that was born a day late. However, if you inserted 2 observers from your Multiverse into these 2 Universes respectively, so that they could both watch the 2 Universes expand and collapse over billions of years, both observers would come back to your Multiverse after the experiment was done and report that yes, indeed they both observed the exact same Universe. Of course, one observer would leave a day earlier, and one would come back a day later, yet still, both once inside your Universe would say they lived the same life for a 100 billion years or whatever.
    So you ask, what's the point of what I just said? The point is this, say the experiment now decides to start one Universe a nanosecond before the other Universe. The experimenter watching the Universes play out again would see that yes, they are very similar indeed, but even a nanosecond is enough time for a photon to travel a great distance in space, so he would have to say that the 2 Universes are different when he takes snapshot pictures of them and compares. Realizing that even a nanosecond is more than enough time to define two Universes as distinctly different, the experimenter devises one last attempt to create two identical Universe's in both space and time. This time the experimenter starts one of the Universes before the second by a time interval of only the 'Planck time' (the shortest theoretical piece of time possible). Finally the experimenter is satisfied that when he studies his instant snapshot photographs of each Universe, that yes, they are in fact not only spatially identical but temporally identical as well.

    I just made that story up quickly, if anyone sees flaws in logic or scientific plausibility please feel free to criticize and correct me. :smile:


  2. jcsd
  3. Feb 7, 2005 #2
    I think you did quite well ----------Multiverse is just too messy--Too complex--so inconsistant with the beautiful simplicity that I feel lies at the foundations of reality.
  4. Feb 25, 2005 #3
    Chaos' lil bro Order,
    I won't respond to the many interesting and inventive scenarios you've created (kudos on imagination, btw), but I will respond to your first statement. You are wondering why there aren't many Multiverses, just as there are many Universes (within the Multiverse framework). Well, think of it this way, the only choice/difference that could be ascribed between Multiverses is whether the Universes within them do what they do at the same time within the separate Multiverse. Since a singular Multiverse has to take into account, all possibilities, it doesn't seem possible for more than one to exist.
  5. Mar 24, 2005 #4

    Very interesting point Mentat.

    I believe I was incorrect on second thought. As you say, by definition, the Multiverse must include all possibilities of all possible Universes, whereas a single Universe only has to include one possibility.

    Here is something I just thought of that may be fruitless but is interesing to ponder for a minute...
    If each grain of sand on a beach is a Universe, and the beach is infinitely large (like the Multiiverse), can there be an infinite amount of beaches?? My response based on what you told me is no. Because the beach by definition spans over everything, therefore it is impossible to break it up into several beaches seperated by partitions.

    It is kind of like saying you can pause infinity at intervals, whereupon new infinites spring up before the first infinity plays again. hmmm my head hurts now. ouch!
  6. Jun 22, 2005 #5
    the point of a multiverse is that it provides the necisary ontology of an infinite/eternal existence- since Existence exists it must have always existed- dealing with just the idea of a singular Universe from the Big Bang as some sort of eruption out of Nothing [ttrue Dimensionless/Formless Nothing- not merely a quantum vacuum state which is NOT nothing] is an absurd and impossible ontology- the only fundamental possibilites are that Existence exists eternally or that true nothing ever exists- since Existence exists it must always be so- [Spinoza/ Hegel]

    a multiverse gives you a rational basis for an eternal Existence while allowing for our universe to have a finite past and beginning in the Big Bang-

    a Big Bang can only make sense if it is an event out of some deeper hierarchy of existence /events- there can be no transistion for true Non-existence to Existence- as it would negate the 'non-existence' in the first place [if Nothing is really Nothing- then it cannot have the property of existence popping out of it- this would define it as SOMETHING]

    it's an unavoidable axiom: Existence exists- therefore it has always and will always exist- but the Big Bang happened- so it must have been an event that caused our universe to emerge from a Multiverse of some kind-
  7. Jun 23, 2005 #6
    I mean what's the use of discussing all these wild guesses? I think humans should try to discover new things that are within the grasp of our technology. Even the multiverse idea cannot be tested why bother about the 'Megaverse'. Remember our genius Einstein who started to look for a Theory that describes both general relativity and electromagnetism fifty years ago? He failed in the end because at that time he did not know about the weak and strong interactions. Perhaps given his high iq, he might be able to formulate the TOE today with the discovery of the other two fundamental force. No one can argue if your speculation is right or wrong because we do not have any evidence - you might be right or wrong. So why bother to delve deeper into an idea that has yet been proven?
    My 2 cent worth. :smile:
  8. Jul 3, 2005 #7

    In one respect I agree with you that there is no reason to delve far into the Multiverse or Megaverse line of thought. We agree that it produces no scientific application and that it is currently beyond the reaches of even the faintest powers of observation or experiment at present.
    However in another respect, I disagree with your notion that its discussion has no merit at all. I think its an interesting question to ask what parameters separate one Universe from the next... If one makes the bold assumption that only the time and space characteristics of one Universe differentiate it from an adjacent Universe, then we can begin to put limits on the scale and scope of all the Universes possible in the larger Multiverse context. For time, perhaps the 'Planck time' is the smallest differentiating temporal characteristic between otherwise identical Universes. For matter, perhaps the 'Planck Mass' is the smallest differentiating material characteristic between otherwise identical Universes. As for the upper limits of a Universe's time and space length and size, who knows. WMAP data can be interpreted as saying time continues forever and the Universe is 'open', or that the gravity with eventually overcome the 'dark energy' and the Universe will 'close' (or collapse if you prefer). The size of space, conversely depends on the push and pull tug of war between 'dark energy-driven' expansion and gravitationally-driven collapse.

    Personally I think trying to contain a problem with limits is the first step in solving an otherwise untacklable question, which is 'How many Universes could possibly comprise our Multiverse?'

    Comments please.
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