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Gross Perrywall phase transition

  1. Dec 14, 2012 #1
    I just watched a video of James Gates and he discussed something he called the Gross Perrywall phase transition. It was named after David Gross, I am assuming most of you are familiar with his work. In an attempt to search more about this I came up empty. I do not know if I am spelling it correctly or not, but I found zero results.

    Does anyone here know what I am talking about? Better yet, any good videos you would recommend along the lines of this?

    Thank you for your time!
     
  2. jcsd
  3. Dec 14, 2012 #2

    Bobbywhy

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    Using the search terms "Gross Perrywall phase transition" in Google Search brings me 450 results, none of which explain the process.

    There is something called "Gross-Neveu phase transition" described in ArXiV 1203.3580. Is that what you described?

    Cheers,
    Bobbywhy
     
    Last edited: Dec 14, 2012
  4. Dec 16, 2012 #3
    Thank you for the reply! I have contacted Dr. Gates and he has informed me that it is spelled "Gross Periwall". I also would like to apologize for being so straightforward and uninformative with what I am seeking to learn. This actually really interests me and I would love to learn more. Here is what I am trying to learn specifically:

    https://www.youtube.com/watch?v=b6w0K5FIgsU#t=47m27s

    The answer he gave here. I have also now found a few papers and a lot of info about perturbation theory but my main interest is about how he describes that at a small enough level actual space begins to disappear?

    I am very familiar with Max Plank's work, but this is a bit different. Unfortunetely I am unfamiliar with most maths used, if anyone had any good references that are "dumbed down" that would be awesome, I especially learn best from videos!

    Thanks again
     
  5. Dec 20, 2012 #4
    Is there a more advanced forum that PF that anyone could recommend? I have searched but not personally found anything better but would really like to get to the bottom of this.

    Bobby, I am thinking it has more to do with one of these papers:

    http://goo.gl/qn07j

    Or something that came from the "Princeton String Quartet".

    Again I am most specifically looking for a layman explanation as to how space begins to disappear at a small enough level as explained in the link I posted above by Dr. Gates.
     
  6. Jun 24, 2013 #5
    ★Advanced: Gross Periwall Phase Transition

    [STRIKE]Posted this in the General Physics forum but got no answers. I am still very intrigued and figured this might be a better subforum to ask.[/STRIKE]

    << Moderator Note -- Two Threads Merged >>

    Question:

    I just watched a video of James Gates and he discussed something he called the Gross Periwall phase transition. It was named after David Gross, I am assuming most of you are familiar with his work. In an attempt to search more about this I came up empty. I do not know if I am spelling it correctly or not, but I found zero results.

    Here is what I am trying to learn specifically:

    http://www.youtube.com/watch?v=b6w0K5FIgsU#t=47m27s

    (The Question at 47:27 into the video)

    The answer he gave here. I have also now found a few papers and a lot of info about perturbation theory but my main interest is about how he describes that at a small enough level actual space begins to disappear?

    Maybe something that came from the "Princeton String Quartet".

    Again I am most specifically looking for a layman explanation as to how space begins to disappear at a small enough level as explained in the link I posted above by Dr. Gates.

    Thanks in advance!
     
    Last edited by a moderator: Jun 25, 2013
  7. Jun 25, 2013 #6

    fzero

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    I think Gates is confusing references here. The behavior he is referring to is a result of Gross and Mende on scattering of strings at energies above the Planck scale. What they found was that such processes are dominated by a specific string configuration, which could be described as a surface. If you compute the scale ##x_s## associated with the size of the surface (say as the square root of the surface area), you find that it scales with the energy of the process ##x_s \sim l_s^2 E ##, where ##l_s## is the fundamental length present in the string theory. This means that for energies ##E > l_s^{-1}##, our probes actually get larger than the fundamental scale ##l_s## that we would hope to probe. It is actually impossible to measure distances smaller than around ##l_s## with strings, leading to the concept of a minimal distance. This is discussed, along with other evidence, in this conference talk by Gross, specifically on pages 20-21.

    The famous result by Gross and Periwal is this paper that shows that string perturbation theory is incomplete. Such a result on perturbation theory is interpreted (for example in QCD) as signaling the existence on nonperturbative phenomena. It was subsequently discovered that these phenomena could be described by D-branes. It is actually true that D-branes allow us to probe somewhat shorter distances than fundamental strings (see for example Shenker), but I do not think that this is what Gates meant (or at least it would not be a result to credit to Gross-Periwal).

    Neither of these Gross et al results should really be called a phase transition, but there is a related concept called the Hagedorn transition. This is a rather technical subject, but in the context of strings, it has been interpreted as a phase transition at a high temperature, beyond which very large strings are produced. This is somewhat reminiscent of the Gross-Mende behavior, where large strings are also the dominant configuration at high energies.
     
  8. Jun 25, 2013 #7
    Thank you very much for that answer! It definitely clears things up and is sending me in different new directions in my pursuit for knowledge on this topic.
     
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