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Big bang goes to court

  1. Jun 7, 2004 #1
    If the big bang theory were to be taken to court under the same umbrella as a capital murder trial do you think it would be found guilty or innocent ?

    i.e. Guilty meaning the big bang did occur and inncoent meaning it did not occur.
     
  2. jcsd
  3. Jun 7, 2004 #2

    marcus

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    Big Bang should get Rudy Vaas as defense attourney.
    He is an alert science watcher and journalist.
    have a look at
    "The Duel: Strings versus loops"
    http://arxiv.org/abs/physics/0403112

    This is an english translation of Vaas article in the
    science magazine "Bild der Wissenschaft" roughly
    comparable to "Scientific American"

    In Vaas article check out the parts about Martin Bojowald
    there is some interview with Bojowald.

    At the trial Rudy would call Bojo for expert testimony that
    in fact although all the circumstantial evidence points to
    expansion starting from a state of infinite density, actually
    Bojo will prove, the singularity did not exist
    and the flow of time was not interrupted.

    IIRC there is a rough intuitive explanation of the quantum
    removal of the BB singularity in Vaas article
     
  4. Jun 7, 2004 #3
    If everything came into being all at once, we would not be able to trace the cause of anything. Causality requires that all things start from other things so that there must have been a beginning where all creation started from. If the court is required to respect the logic of causality, then guilty is the only possible verdic.
     
  5. Jun 7, 2004 #4

    marcus

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    great idea! we have a mock trial or "moot court"
    Bozo is the Judge
    and Big is hauled into the dock and charged with the capital crime
    of having Banged
    Mike2 is the prosecuting attorney
    who must prove beyond the shadow of a doubt
    (because it is a capital offense)
    that Big banged

    Rudy Vaas rises to address the court in defense of Big
    Your honor the old version of GR encountered a moment of
    infinite density when it was extrapolated backwards to the
    beginning of the observed expansion
    and that infinite density represented a breakdown where the theory fails to compute. (when a theory breaks down it's called a "singularity" even if it happens at a whole continuum of points, singular doesnt mean single it means odd, peculiar, irregular)

    Your honor I shall call an expert witness to the stand, one Doctor Bojowald of Berlin, who will show that the glitch in GR can be fixed, by quantizing the Friedmann equations, so that the theory can be extrapolated smoothly back in time to before expansion began. this up-dated version of GR predicts inflation and also predicts a prior contractive stage and it eliminates the classical GR singularity.

    Therefore, despite all appearances to the contrary, Big did not bang.
    My respected colleague Mike2 will not, your honor, be able to show beyond shadow of doubt that Bang is guilty!

    "The Duel: Strings versus loops"
    http://arxiv.org/abs/physics/0403112
     
    Last edited: Jun 7, 2004
  6. Jun 7, 2004 #5
    ah- but which BBT will be brought before the judge and jury? a "bang- less" de Sitter universe? ekpyrotic brane collisions? infinite inflation? Two Big Bangs? the good old-fashioned expansion from a singularity? black hole reproduction/selection? there are as many concepts about the BB as there are physicists almost-

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    Last edited: Jun 7, 2004
  7. Jun 7, 2004 #6

    Phobos

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    A jury trial? 12 people selected with no prior knowledge of the debate? Who knows. They do wacky things sometimes.

    A supreme court type deal? They would probably be satisfied to keep it on the books. For example, they upheld the theory of evolution as a valid scientific theory.
     
  8. Jun 7, 2004 #7
    Witten proved that a universe can only expand from a singularity, a single point, where space AND time go to zero. Can the energy of a previous universe pass through such a point? Can energy be expressed where there is no space and no time? I think not. Whatever prior universe might have existed is completely irrelevant to our universe, nothing from it has ever had any affect on us. Nothing in our universe was as a result of any alledge prior universe. I move the the prior statement be stricken from the record.
     
  9. Jun 7, 2004 #8

    Njorl

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    It is extremely rare for there to be a finding of innocent in a court. It is possible, but almost never even sought. "Not guilty" is generally good enough for those involved. A finding of innocent has the reverse constraint - there must be no reasonable doubt of innocence.

    Njorl
     
  10. Jun 7, 2004 #9

    marcus

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    Mike2 in what publication of Witten's is this proven?
    Please give a reference :smile:
     
  11. Jun 7, 2004 #10
    I was mistaken, sorry. Alan H. Guth in his book, The Inflationary Universe, page 265, writes,
    "According to the Penrose theorem, rapid collapse without a subsequent singularity is impossible. Reversing the direction of time, if follows that rapid expansion without a preceding singularity is also impossible. In this form the theorem applies to the false vacuum bubbles. For the bubbles to expand fast enough to become a universe, Penrose tells us that it must begin from a singularity."

    Technically, this is hearsay evidence. But it refers to a principle which you are free to look up and consider for yourself.
     
  12. Jun 7, 2004 #11

    marcus

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    and the single point?

    do you have a reference for that?
    Your quote from Alan Guth only says "singularity" which
    could mean a singularity of infinite 3D spatial extent...
     
  13. Jun 8, 2004 #12

    russ_watters

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    For the original question, let me frame it this way: would a panel of 12 scientists who had never heard of the BBT (yeah, I know, not possible) find beyond a reasonable doubt that the Big Bang happened. I believe so.

    The question of whether or not there was a Big Bang really just comes down to "do you accept that redshift = expansion?" If yes: BBT. If no: no BBT.
     
  14. Jun 8, 2004 #13
    No. I only have Alan Guth's quote. But in context, I think it is clear that he meant a single point.
     
  15. Jun 8, 2004 #14

    marcus

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    well, please quote the context!

    it is very strange, because you seem to be claiming that Roger Penrose
    proved mathematically that the universe expanded from a point!

    Now I dont know of any cosmologist who believes that there is a mathematical proof of that.
    It is usual to assume that the initial singularity may have been infinite in extent.

    there are very special assumptions under which one can prove that it expanded from a point, but no guarantee that these assumptions correspond to reality!
    so the usual thing to assume is that (although one does not know) it may have expanded from a singularity of infinite extent.

    I suppose that Roger Penrose did not prove mathematically that under general assumptions the U expanded from a point, because how could he mathematically prove something wrong?

    so maybe Penrose was talking about something else or making some
    very special assumptions, or perhaps Guth is not reporting Penrose result in enough detail

    there can be, I guess, several possible explanations.

    So why dont you just quote several sentences to give the context that you think makes it clear that Guth thinks that Penrose thought it was from a single point?
     
  16. Jun 8, 2004 #15

    jcsd

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    Though most people would associate gravitational singularities with single points (after all another word for a singularityin maths is a 'singular point'), it doesn't mean that the initial singularity was a single point. Though it must of been a single (spatial) point in a finite univerese it couldn't of been a single (spatial) point in an infinite universe.

    Out of ineterest you can 'go through' the singularity to a 'prior universe' in a highly idealized big bang model.
     
  17. Jun 9, 2004 #16
    Mike refers to the Hawking-Penrose singularity theorem, devised by these two scientists (and good friends) in 1970. This theorem demonstrates that the universe started in a singularity.
    Myron Evans is very harsh with the theorem in this page
    http://www.aias.us/Comments/hawkingpenrose.html

    Given that i haven't read the original paper, I cannot tell what was meant by "singularity" in the theorem. It could seem that singularity is a thing of zero volume. Though there are other people that claim that a singularity can have an infinite volume
     
  18. Jun 10, 2004 #17

    marcus

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    Hawking and Penrose, "The Singularities of Gravtitational Collapse and
    Cosmology", Proceedings of the Royal Society (London) A, 314, 519-548.


    I havent read the original hawking-penrose paper either, but I've looked at the statement of the theorem and it says nothing about the singularity being limited to a single point

    discussions of the H-P singularity theorem which I've seen refer to a region of singularity---nothing I've seen suggests the region of singularity cannot have infinite extent

    the actual theorem proves the existence of at least one incomplete timelike geodesic (under certain conditions)
    that is, at least one geodesic runs into trouble

    but it does not rule out what we see happening in familiar models in cosmology which is that a whole bunch of geodesics run into trouble
    at an infinite 3D hypersurface-----that whole infinitely extending hypersurface is a singularity

    this word "singularity" meaning oddness or weirdness or irregularity
    (but confusing people because it sounds like "singleness")

    has caused a lot of trouble

    that fellow Myron seems rather singular himself----am I mistaken? I didnt
    take much time and first impressions are not always fair.
     
  19. Jun 10, 2004 #18
    I found this page
    http://www.qsmithwmu.com/time_began_with_a_timeless_point.htm
    "According to the Friedmann equations and Hawking-Penrose singularity theorems that determine the basic physical laws of our universe, spacetime must begin in a singularity, i.e., as an “explosion” of a singular point"

    I'm not saying that that is what happened. After all, Quentin Smith, the author of the article, could be the major crackpot in internet: I've never heard of him or any of his publications. I just googled in "Hawking-Penrose singularity theorem"+"point" and appeared to me this. So, given that is impossible for me to read the original article, I've decided that the best thing to do is to e-mail to the authors, Stephen Hawking and Roger Penrose, and ask to them. That's what I'm going to do
    this is Hawking's e-mail
    S.W.Hawking@damtp.cam.ac.uk
    and this is Penrose's
    rouse@maths.ox.ac.uk
     
  20. Jun 10, 2004 #19
    If you are finding difficulties to find info about the Hawking-Penrose singularity theorem (there're not much entries in google) it may be helpful to know that the theorem goes also by the name of Hawking-Penrose theorem or Penrose-Hawking singularity theorem)

    marcus, Evans is generally seen as a fringe scientist. He has a also an own theory of electromagnetism
     
  21. Jun 23, 2004 #20
    This can be interesting (or not). I've had recently the opportunity to read "The elegant universe", and B.Greene says that in the Big bang model the universe emerged from a point, and there wasn't nothing outside the point:
    "Extrapolating all the way back to "the beginning," the universe would appear to have begun as a point—an image we will critically re-examine in later chapters—in which all matter and energy is squeezed together to unimaginable density and temperature. It is believed that a cosmic fireball, the big bang, erupted from this volatile mixture spewing forth the seeds from which the universe as we know it evolved.

    The image of the big bang as a cosmic explosion ejecting the material contents of the universe like shrapnel from an exploding bomb is a useful one to bear in mind, but it is a little misleading. When a bomb explodes, it does so at a particular location in space and at a particular moment in time. Its contents are ejected into the surrounding space. In the big bang, there is no surrounding space. As we devolve the universe backward toward the beginning, the squeezing together of all material content occurs because all of space is shrinking. The orange-size, the pea-size, the grain of sand-size devolution describes the whole of the universe—not something within the universe. Carrying on to the beginning, there is simply no space outside the primordial pinpoint grenade. Instead, the big bang is the eruption of compressed space whose unfurling, like a tidal wave, carries along matter and energy even to this day."
     
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