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Are There Other Universes?

  1. Jul 28, 2004 #1
  2. jcsd
  3. Jul 29, 2004 #2
    Yes, our universe has always been that way. Just a small speck in an even greater universal force. However, you speak of other universes as though they are all connected to ours, but just so far away that we are unable to detect them.

    What of Parallel Universes then? Universes that exist in the same universal plane as us, but in a different dimension. So that where we are now actually consists of millions of other universes, but we cannot touch/feel/see them because their in a dimension that we cannot detect.
     
  4. Jul 29, 2004 #3
    see string theory
    good luck
    jamie
     
  5. Jul 29, 2004 #4

    Chronos

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    The quantum fluctuation concept is very appealing. It certainly possible that a huge number of 'false starts' occured 'prior' to this universe. Some could have immediately recollapsed, others may have flown apart so rapidly that no galaxies, stars, or sentient being to behold them had a chance to form. A few happened to have the right balance to endure and evolve similar to this one. Many of those, however, may not have had the right properties to permit sentient life to evolve, hence, are effectively empty. Without observers to collapse the waveforms into objective reality, they are a chaotic, quantum stew of simultaneous possibilities.. ghosts without substance. It seems improbable any such other 'universes can communicate with each other. Each would have its own unique rules and content which would have not meaning outside those rules [ie, cannot interact with 'foreign' content]. Think of it as a match pitting a football team against a volleyball team with each side playing by the rules of their game. No meaningful outcome would result.

    The relevant question is what, if any interaction do other universes have with this universe. If none, they are irrelevant and can be excluded from consideration by applying Occam's Razor. If they do interact, then only the interacting features would be detectable by observers in either universe. And each observer would justifiably conclude the features of the 'other' universe interacting with their own was an extension of their universe. The non-interacting features would be forever hidden from each other. This has important theoretical implications. It may well be that certain properties of our universe can only be defined empirically. The ultimate explanation of why they are as they are may exist in regions of the 'multiverse' that are impossible for us to observe. If this is the case, a truly complete TOE is unachievable.
     
    Last edited: Jul 29, 2004
  6. Jul 29, 2004 #5

    turbo

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    The anthropic principal is fun to contemplate for a minute or two, but badly flawed. Here is a link to one site that discusses the anthropic principal (there are thousands):

    http://www.geocities.com/lungdoctor_tn/Anthropic_Principle.htm

    Let's point out a little flaw in the principal. For MANY years (almost all of the life of the Earth), there was no sentient life on Earth. Can anyone rationally deny the existance of the Universe during the time when humans were NOT on Earth? Now consider this: If I die will the Universe cease to exist for you? I think not. If an asteroid slams into our planet or a nearby star goes supernova and sterilizes our planet of all life, will the Universe cease to exist? That's quite a conceited, misguided view of the Universe - that we as humans are at the center of everything and that our mere contemplation of the Universe is a necessary condition for the existence of that Universe.
     
    Last edited: Jul 29, 2004
  7. Jul 29, 2004 #6

    Chronos

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    The anthropic principle is not a law of nature. It is, however, a valid means to test theory. If we make an observation that precludes our existence, the observation or assumptions used to arrive at that conclusion must be flawed. We routinely use similar principles in the same manner: the atomothropic principle [observations that preclude the existence of atoms are flawed], the cosmothropic principle [observations that preclude the existence of the universe are flawed]. The anthropic principle is convenient because it relies on an assumption that most everyone understands and agrees with.. I am certain that I exist, and I am nearly certain that you exist.
     
  8. Jul 29, 2004 #7

    turbo

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    The anthropic principal is not a valid scientific tool. It is a flawed philosophical viewpoint - a set of half-baked assumptions and a statement that if WE cannot exist without certain preconditions, therefore the Universe cannot exist without the same set of preconditions. This is a particularly silly tautology. Decartes used his perception of his own existence as the foundation for his philosophy, but it was a logical argument only (albeit very dangerous in a world dominated by the Roman Catholic Empire), and even he would not have been so presumptuous as to suggest that if HE ceased to exist, the Universe would cease to exist. My ferret exists, and I love him dearly, but the sun is not going to stop shining when he dies. My wife exists and I am absolutely devoted to her, but the the sun is not going to stop shining when she dies, nor shall it go dark when I die. Those who ascribe the existence of the Universe to the existence of ourselves, or our species, are "not firing on all cylinders" to be polite.

    I'll be willing to consider alternative viewpoints, providing you supply the math to suport your position. :wink:
     
  9. Jul 30, 2004 #8

    Chronos

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    The anthropic principle is not predictive, it is preemptive. It merely excludes explanations that forbid our existence. The math supporting that position is 1=1. If we conclude we exist, that is the assumption. Any and all predictions that follow hinge upon the validity of that assumption .
     
    Last edited: Jul 30, 2004
  10. Jul 30, 2004 #9

    turbo

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    The Anthropic Principle is usually applied in a tautological manner and is frequently used by Creationists to "prove" that the Universe was created expressly for Man. They point to all the "coincidences" that "prove" that God created the Universe in such a way as to provide for us, while ignoring the fact that life has evolved and adapted itself to take best advantage of the extant conditions of this Universe. Natural selection is pretty well established by now, don't you think? It always eludes these people, though. It's pretty sad.
     
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