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Videos from Planck Scale conference now online

  1. Jul 18, 2009 #1

    marcus

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    http://www.ift.uni.wroc.pl/~planckscale/movie/

    The first one I intend to watch is Steve Carlip's
    He is talking about similarities that have emerged among different approaches to QG.
    In particular evidence for reduction of dimensionality as you zoom in (inspect the spacetime geometry at smaller and smaller scale.)

    Oh! Carlip's talk was on day 1 and they say they still have some technical problem with day 1, so far the videos from day 2 thru 5 are the only ones available.
     
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  3. Jul 18, 2009 #2
    Did you attended the conferences? I guess I read it before from you in another post. It's nice they put the videos... I was in the workshop in Valencia (my first time) and Barbero told they would put the videos in the same page, but I don't see them anywhere.
     
  4. Jul 19, 2009 #3

    marcus

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    Regret to say I did not attend. But the videos are great! I have now watched many of the presentations and also one of the two discussion sessions: the Tuesday one chaired by Hermann Nicolai.

    I was interested to hear that you went to the Valencia workshop on LQG+Black Holes. Did any talk or talks stand out for you there?
     
  5. Jul 19, 2009 #4

    atyy

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    Why is Jupiter beyond the Planck scale? :confused:
     
  6. Jul 19, 2009 #5

    marcus

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    You could be referring to the graphic header on the home page of the conference. A uniform grid of hexagons superimposed over a complex irregular natural background. Does anyone have any ideas of how to explain that graphic?
     
  7. Jul 19, 2009 #6

    atyy

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    I was being facetious :biggrin: and talking about the musical header:

    http://www.ift.uni.wroc.pl/~planckscale/movie/index2.html



    The bringer of jollity :smile:
     
    Last edited by a moderator: Sep 25, 2014
  8. Jul 19, 2009 #7

    marcus

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    By Jove! So that was the "Jupiter the bringer of jollity" section of Gustav Holst' music, The Planets.
    I suppose the connecting idea is "space". The conference was about space (space under a microscope) and The Planets is categorized by many people along with Strauss Zarathustra 2001 segment as space music. To me it was a mismatch. Assuming they wanted classical music to begin and end each recorded lecture, can you think of something you'd have liked better?
     
    Last edited: Jul 19, 2009
  9. Jul 19, 2009 #8
    I also regret that I did not presented anything, but I'm also ethusiast about LQG and hope in the near future would be giving any modest aportation.
     
    Last edited: Jul 20, 2009
  10. Jul 19, 2009 #9

    atyy

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    I initially thought it wasn't suitable, but changed my mind after the extraordinary background at end of Jupiter (, 7:18-7:34) reminded me of Wen's pictorial depiction of long-range entanglement (http://pirsa.org/index.php?p=speaker&name=Xiao-Gang_Wen, 57:43).

    Then I wondered whether music is background dependent or not. The standard notation has a fixed metrical (in the musical sense) background, and this is maintained in some performances, even with rubato, eg. Mozart's "I am always strictly in time. They all wonder at that. They cannot understand how I keep the left hand independent in the tempo rubato of an adagio, for with them the left hand always follows the right." However, I wondered whether this was true in performance across the entire section of the famous Jupiter tune (3:08-4:57) - I imagine that little segments might be well approximated by a "cartesian" metric, but not large segments. Of course, this only means that the spacetime is not flat, but curved - the background independence comes by the fact that it is the particular arrangement of notes in melody and harmony that determines the appropriate rubato.

    So I looked up "differential geometry and music" and found http://books.google.com/books?id=6I9U9-Rls8oC&source=gbs_navlinks_s - which made me now want to understand what Chris Isham is up to nowadays http://arxiv.org/abs/0803.0417 :smile:
     
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  11. Jul 21, 2009 #10

    marcus

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    The Day One talks are now available.
    Of particular interest, I thought, were those of Steve Carlip and Hermann Nicolai. Also Renate Loll, Fotini Markopoulou, Martin Bojowald.
     
  12. Jul 22, 2009 #11

    marcus

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    Hermann Nicolai's talk was very interesting.
    http://www.ift.uni.wroc.pl/~planckscale/movie/
    It covered work on a possible way of extending the Standard Model all the way to planck scale with a minimum of complications---stressing econony. Work with Kris Meissner, one of the two people who organized the conference.

    http://arxiv.org/abs/0710.2840
    Effective Action, Conformal Anomaly and the Issue of Quadratic Divergences
    Krzysztof A. Meissner, Hermann Nicolai
    17 pages
    (Submitted on 15 Oct 2007)
    "For massless phi4 theory, we explicitly compute the lowest order non-local contributions to the one-loop effective action required for the determination of the trace anomaly. Imposing exact conformal invariance of the local part of the effective action, we argue that the issue of quadratic divergences does not arise in a theory where exact conformal symmetry is only broken by quantum effects. Conformal symmetry can thus replace low energy supersymmetry as a possible guide towards stabilizing the weak scale and solving the hierarchy problem, if (i) there are no intermediate scales between the weak scale and the Planck scale, and (ii) the running couplings exhibit neither Landau poles nor instabilities over this whole range of energies."

    http://arxiv.org/abs/0803.2814
    Neutrinos, Axions and Conformal Symmetry
    Krzysztof A. Meissner, Hermann Nicolai
    10 pages, 2 figures, Eur.Phys.J.C57:493-498,2008
    (Submitted on 19 Mar 2008)
    "We demonstrate that radiative breaking of conformal symmetry (and simultaneously electroweak symmetry) in the Standard Model with right-chiral neutrinos and a minimally enlarged scalar sector induces spontaneous breaking of lepton number symmetry, which naturally gives rise to an axion-like particle with some unusual features. The couplings of this 'axion' to Standard Model particles, in particular photons and gluons, are entirely determined (and computable) via the conformal anomaly, and their smallness turns out to be directly related to the smallness of the masses of light neutrinos."

    http://arxiv.org/abs/0809.1338
    Renormalization Group and Effective Potential in Classically Conformal Theories
    Krzysztof A. Meissner, Hermann Nicolai
    17 pages, 2 figures
    (Submitted on 8 Sep 2008)
    "We derive a general formula for the RG improved effective (Coleman-Weinberg) potential for classically conformal models, applying it to several examples of physical interest, and in particular a model of QCD coupled via quarks to a colorless scalar field. The closed form expressions allow us to discuss the range of validity of the effective potential as well as the issue of 'large logarithms' in a way different from previous such analyses. Remarkably, in all examples considered, convexity of the effective potential is restored by the RG improvement, or otherwise the potential becomes unstable. In the former case, symmetry breaking becomes unavoidable due to the appearance of an infrared barrier LambdaIR, which hints at a so far unsuspected link between LambdaQCD and the scale of electroweak symmetry breaking."

    http://arxiv.org/abs/0907.3298
    Conformal invariance from non-conformal gravity
    Krzysztof A. Meissner, Hermann Nicolai
    (Submitted on 20 Jul 2009)
    "We discuss the conditions under which classically conformally invariant models in four dimensions can arise out of non-conformal (Einstein) gravity. As an 'existence proof' that this is indeed possible we show how to derive N=4 super Yang Mills theory with any compact gauge group G from non-conformal gauged N=4 supergravity as a special flat space limit. We stress the role that the anticipated UV finiteness of the (so far unknown) underlying theory of quantum gravity would have to play in such a scheme, as well as the fact that the masses of elementary particles would have to arise via quantum gravitational effects which mimic the conformal anomalies of standard (flat space) UV divergent quantum field theory."

    Suppose you wanted to choose three talks that could serve to "triangulate" the current main direction of the effort to formulate planckscale models of geometry and matter. To extend both the Standard Model and General Relativity to high energy density/small scale. What recent lectures would you choose?

    I think I would pick:

    Steve Carlip ( 29 June at the Planck Scale conference)
    Hermann Nicolai (also 29 June at the Planck Scale conference)
    Steven Weinberg (7 July at Cern)

    For Weinberg start at minute 58 of this talk: http://cdsweb.cern.ch/record/1188567/ or watch the first 58 minutes as well, for history and context.
    The other two are at:
    http://www.ift.uni.wroc.pl/~planckscale/movie/
     
    Last edited: Jul 22, 2009
  13. Jul 23, 2009 #12
    The same videos are also available through page with better usability:

    http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php [Broken]

    Ps. Theme song was chosen by IT guys by random... No special philosophy behind it :)
     
    Last edited by a moderator: May 4, 2017
  14. Jul 23, 2009 #13

    marcus

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    Thanks to Remi Durka and/or Thesamer for posting the talks in a more convenient form.
    At the main site there is a slight inconvenience that if, for example in day 3, if one stops a talk before the end, and wants to switch to another talk on the same day, then there will be some slowdown unless one closes the whole movies window and reopens it fresh. It is easy to cope with it if one just closes and reopens fresh.

    I have a lot of respect for Kris Meissner and Jerzy Kowalski-Glikman for organizing this conference. It was a smart idea to put together guiding people from several approaches (Loop, String, GRenormalization, Triangulations, Meissner/Nicolai conformal SM extension, Graphity).

    Do you know Meissner? Here is his homepage:
    http://www.fuw.edu.pl/~meissner/home.html

    He has one or more highly cited papers in Loop Quantum Gravity, and several in String, and also he is collaborating with Nicolai on this very interesting economical extension of the Standard Model to Planck scale. Here are his recent papers---"date > 2002" meaning from 2003 - 2009.
    http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+A+MEISSNER%2CK.+AND+DATE+%3E+2002&FORMAT=www&SEQUENCE=citecount%28d%29 [Broken]

    Before 2003 his work was mainly in String. Multifaceted guy.
    I am beginning to see an emigré community become increasingly prominent.
     
    Last edited by a moderator: May 4, 2017
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