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Origin of Space and Time

  1. Jul 24, 2005 #1
    I have read that not long after the BB (~10-32 sec) time and space, as we define them, separated from a unified "whole" which they were a part of. Now its entirely possible that I just misrepresented what I read and if this is the case then I apologise for wasting everyones time.

    But if my interpretation is by and large accurate, isnt that just a way of saying that before time and space broke off, there was no time and space? I.e. the there was 0 space between matter even at the smallest level (smaller than superstrings I guess) so does this mean that the universe was a single point with 0 dimensions? With 0 space there is nowhere to travel to because there is just 1 co-ordinate so is it reasonable to assume that if time is dependent upon space there cant be any time withtout space?

    Is this a reasonable representation of time and space just before they came to be?

    Again if my argument is off its because I have no no formal training in physics whatsoever so any constructive criticism would be greatly appreciated.
     
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  3. Jul 24, 2005 #2

    turbo

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    A quote from "Lonely Hearts of the Cosmos" by Overbye. Stephen Hawking told Overbye "There are no singularities if the metric in the path integral but there are singularities in the classical solutions the correspond to the wave function." It may be that the BB singularity will disappear when we learn how to accurately describe the universe in terms of quantum physics. Hawking in the 1980s announced a no-boundary proposal to remove the BB singularity-it was not a popular idea. The idea that we can create more and more powerful particle accelerators to push back our understanding of the extremely early universe is beguiling, but may be misguided. We have not yet found any SUSY partner particles, nor any Higgs bosons, nor any gravitons. Perhaps it is time to look at the quantum vacuum and probe its qualities. If a tiny vacuum fluctuation can give rise to an entire universe in the BB model, it might be a good time to consider whether the quantum vacuum could have substantial effects in our observable universe.
     
    Last edited: Jul 24, 2005
  4. Jul 24, 2005 #3
    In reference to the entire universe anything on a quantum scale is going to appear "tiny". But when the universe was a point a billion billion times smaller than a proton then something that tiny would be anything but on that scale. I think the problem lies in that our brains are limited in that we can only visualize 3d space and time. Some ppl can conceptualize 1 or 2 more dimensions max. But to take it any further than that, you need to use math. But even with math its like trying to find a needle in the haystack in that its a hit-miss proposition from the get-go. Its one thing to be able to use real world scenario's to work out theories such as considering what a beam of light shining down from a light fixture in a train looks like to a passenger in that train versus what it looks like to an observer standing on the platform outside as the train is blowing by, but its an entirely different proposition to try to conceptualize scenarios in other dimensions in order to help focus your thoughts. Our brains just arent built that way.
     
    Last edited: Jul 24, 2005
  5. Jul 24, 2005 #4

    Chronos

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    3+1 dimensions work just fine for me. More than that... I need to see the evidence, any evidence, that 3+1 does not describe the universe we observe. Compactified dimensions? My doctor gave me a prescription for that.
     
  6. Jul 25, 2005 #5
    ...your point might very well foreshadow the fact that we might never see, fully comprehend and ultimately engage anything outside of the box we call our universe...

    the over the counter stuff just wasnt cutting it anymore was it....I feel your pain man...


    jk bro...cheers...
     
  7. Jul 25, 2005 #6

    turbo

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    In some variants of string theory, you will need LOTS of dimensions, perhaps a couple of dozen. This does not bode well for GUTs, since we live in a world that is pretty demonstrably 3+1 dimensional. When a mathemetical theorist tells us that he can model the universe perfectly, but not in ten dimensions, but in eleven dimensions, I cannot run out into the streets and celebrate. I find it much more likely that we will find success in an offshoot of loop quantum gravity. An offshoot in which the fine structure of space is dominated by the quantum vacuum, and in which gravity is not a fundamental force, but is emergent. We don't need to consider extra dimensions - the ones we have are complex enough and rich enough to unite GR gravity with quantum theory.

    The concept that time and space suddenly "came to be" (from your initial post) may need to give way to the concept of infinity of space and time. Mathematics is shot through and through with infinities, and they crop up constantly in quantum theory, only to be beaten back by renormalization techniques. Dirac was very dismissive of this, and said that it belied an ignorance in the way things acted at quantum levels. He said that it was permissable to ignore a value because it was very small and had little effect on the outcome of your calculations, but that it was irresponsible to ignore a value because it is infinitely large and you do not want it. I don't have the exact quote, and he surely stated it more succinctly and elegantly, but you can be sure that the unwanted infinities in quantum theory are pointing us to some fundamental truths that we do not yet grasp.
     
  8. Jul 26, 2005 #7

    Chronos

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    Agreed. There is still no workable theory of 'prior' states. Not string, loop, or CDT comes to the table with any satisfactory explanation, at least in my mind. Thoughts?
     
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