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No Boundary Idea of Universe

  1. Mar 2, 2004 #1
    Everyone keeps discussing some forms of the big bang models for the creation of the universe, however upon reading hawkings The theory of everything, he discussed many models for the creation of the universe. One, that i found particularlly interesting was the idea of the No-Boundary Universe, in which the unverse is shaped like the outside of the earth, allowing you to go around the universe and end up in the same point in which you started. It seemed to me upon the completion of the book that Hawkings seemed to like this theory and maybe would be considered his current thought of the beginning when the book was published. I was wondering if there was any new news about the no-boundary model?

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  3. Mar 2, 2004 #2


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    I don't know if this makes trouble for the no-boundary proposal, but modern studies of the skies show the universe is flat as far as the eye can see (except for local gravity wells of course). The degree of flatness is also extreme, and stresses our understanding of basic physics.
  4. Mar 11, 2004 #3
    ofcourse but the eye cannot see so far as to reject a no-boundary model and from a point of view this model sounds reasonable, but then... people always have a drift of using familiar models (from everyday life) to explain something unknown.
  5. Mar 12, 2004 #4
    well, there is no 3 dimentional bountry, but there is a 4 dimentional bountry,
  6. Mar 12, 2004 #5

    if the Universe were a hypersphere, and we were 3d beings living on the surface of the hypersphere, we would not see a curvature to space just like a flatlander would not see a curvature of a sphere he lived on.

    also, there is a reason that when we look out into the universe in ultra deep feild studies that we see proto galaxies, etc., it is because we are looking toward the center of the hypersphere and see the universe as it was.

    since our local sensory input is based on our experience in 3d world, and out deep views are based on time, it make sence that localy we see nothing to indicate curvature, and since time is flat and smooth, when we look back to the beginings of the universe, we see flat curvature.

    hmm...I just had an interesting thought about travel through space.

    space is expanding perpendicular to time.

    that is why we see light from 100,000 years ago. otherwise, if time was parralel with space, travel around the universe would not be a problem, or if space was expanding at some angle other than perpendicular to time, you would have a diffrence function os movment through space with relation to time than we have.

    so, in order to get to another location in the universe quicker, rather than travel along the space vector, we need to travel through the time vector, at least a little bit.

    wow...it is interesting to look at travel through space-time from that perspective.... sorry for the half OT comment.
  7. Mar 12, 2004 #6


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    "Looking toward the center of the hypersphere?" No, we live and see only in the hypersurface of that hypersphere, if you get my drift. Think of all the light rays as lines trawn on the taut surface of the analogous balloon. And as for the perceived flatness, this goes far beyond the ant on the balloon analogy because the microwave background gives us a kind of record of the past, and that confirms the flatness.
  8. Mar 12, 2004 #7
    well, that is one way to see it, however, you do not take into account the path over time.

    if you take the path of the light over time, you get a streight line from below the surface of the hypersphere where and when the event occured to earth on the surface of the HSphere, so we are looking into the hypersphere.
  9. Jun 16, 2004 #8
    This has another name

    Your theory has another name modmans, it is Kaluza Klein theory.

    To the original poster, Hawking defineately likes the No boundary because he did discuss it with the pope (and good thing that the pope did not know what Hawking was implying with NB, there is no creator).
  10. Jun 20, 2004 #9
    some say that are universe is 1 dimensional to the third power, and exists in a straight line, expanding from either side into infinity
  11. Jun 23, 2004 #10


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    ..untill next barrel of vacuum energy we are sitting on explodes and puts stop to the existance of the universe as we know it.Perhaps~pretty probably~perhaps~pretty probably...
  12. Jun 23, 2004 #11
    Dimesnionless universe

    The universe is probably dimensionless and time and space(spacetime) is an illusion caused by the introduction of measurement, which in turn would make time and space a psychic (mental) phenomena (for that matter the universe as a whole might be a psychic phenomena but my views may be bias since I am an idealist not a materialist). The nonlocality of subatomic particles SUGGEST (not proves) this. If you find these concepts interesting I suggest reading the basic writings of physicist David Bohm. Physicist F. David Peat also has some interesting ideas on these subjects and he has a website that can be found on a search engine by simply typing in his name.
    The famous physicst John A. Wheeler believes consciousness plays a central role in the universe but he (like a lot of physicists) tends to keep his metaphysical views close to his chest in the public eye.
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