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2008 Large Grant FQXi Awardees

  1. Aug 5, 2008 #1
  2. jcsd
  3. Aug 12, 2008 #2

    marcus

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    I think there's stuff we can learn from studying some of these proposals. the one that stands out for me, right now, is the Penn State troika (AAB = Alexander, Ashtekar, Bojowald)
    http://www.fqxi.org/large-grants/awardee/details/2008/alexander
    Be sure you click on the technical abstract link, so you get more detail

    Awardee:
    Stephon Alexander, Pennsylvania State University
    Project Title:
    Foundational Questions in Cosmology and Quantum Gravity
    Co-Investigators:
    Abhay Ashtekar, Pennsylvania State University
    Martin Bojowald, Pennsylvania State University
    ==quote==
    Summary:
    This proposal requests support for research on five projects at the interface of cosmology, quantum field theory, quantum gravity and conceptual foundations of physics. The overall goal is to seek new physical and potentially observable effects by exploiting the tension between deep conceptual issues in fundamental theories. Specifically, we will analyze notions of time that can emerge in the cosmological context and their physical implications, study the possibility that the weak force and the observed violation of mirror symmetry in Nature may originate in quantum effects of gravity, explore the origin of the arrow of time, investigate how information can leak out of black holes, and analyze whether multiverses can naturally arise in quantum gravity evolutions. This research will be carried out by three PIs (Stephon Alexander, Abhay Ashtekar and Martin Bojowald) with the help of students and post-docs each of whom will spend 2 - 3 weeks on specific aspects of these projects.

    Technical Abstract:
    This proposal requests support for research on five projects at the interface of cosmology, quantum field theory, quantum gravity and conceptual foundations of physics. The overall goal is to seek new physical and potentially observable effects by exploiting the tension between deep conceptual issues in fundamental theories. Specifically, we will explore the following issues:

    i) Unexpected implications of `internal' time one is naturally led to use in generally covariant theories;

    ii) The possibility of unifying the microscopic weak force with large scale cosmological evolution using a novel approach;

    iii) Fundamental problems associated with entropy and arrow of time in cosmological models in which the big bang singularity is resolved;

    iv) Explanations of why entropy is not lost in the black hole evaporation in space-time terms; and

    v) Whether multiverses can emerge dynamically in loop quantum gravity and, if so, how one can calculate the probabilities of their emergence from first principles.

    This research will be carried out by three PIs (Stephon Alexander, Abhay Ashtekar and Martin Bojowald) with the help of students and post-docs each of whom will spend 2 - 3 weeks on specific aspects of these projects.

    ==endquote==

    Points iv) and v) in the Technical Abstract correspond to what I bolded in the Summary and point, at least in part, to Smolin's falsifiable multiverse conjecture.

    the conjecture is that standard model parameters are at a local peak for black hole production.

    Regarding point iv), one possible explanation that one expects might be considered is that information is not lost because it flows into an offshoot baby universe.
    That is, there is no black hole information paradox (Hawking wager hullaballoo notwithstanding) because time forks at gravitational collapse.

    The process of black hole bounce is becoming better understood in the Loop gravity context---several papers about this in the past two years---a good one to look at is by Vandersloot and Boehmer---they found a Nariai universe issues from the pit (and that may not be the end of the story.)
     
    Last edited: Aug 12, 2008
  4. Aug 12, 2008 #3

    marcus

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    This point iii) of the technical abstract deserves special consideration:

    iii) Fundamental problems associated with entropy and arrow of time in cosmological models in which the big bang singularity is resolved;

    the main cosmological model where the bigbang singularity is resolved (with a bounce) that people are working on these days is the Loop Cosmology model. There are a lot of papers on this, especially in the last two years.

    And a fundamental issue they have to consider is something we could call Penrose Objection.

    If you consider entropy as something absolute, not observer-dependent, but something seen by an Eternal Eye :wink:, then there appears to be a violation of SECOND LAW when a universe collapses in a crunch and there is a bounce leading to a new beginning.

    Because it appears to reset the entropy clock, back to zero. Sir Roger Penrose claims this is a fatal objection to the bounce. But in rebuttal one could say that to actually witness the violation an observer would have to be outside the universe.

    (IOW real observers, including any hopeful of patenting perpetual motion machines if they can ever find a violation of thermodynamics, are always either before or after the bounce---so they never get to witness a violation.)

    It is a really interesting question and makes me think that the Alexander project is exactly the sort of thing that FQXi should be funding.
     
  5. Aug 12, 2008 #4

    marcus

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    I have a hunch that we can learn something by studying the summaries of the projects that FQXi funded. Unfortunately this information goes away after a few months!
    The 2006 awards are no longer online!
    Now we have a new set, the 2008 awards---apparently it is a 2-year cycle---but comparison with 2006 is not convenient.

    The FQXi science advisory board has some people like Lee Smolin and Frank Wilczek on it IIRC, and the institute has a creative mission---to promote research too edgy to get conventional gov. grants but which is still real science. In the screening process they recruit some notable people to help them. We should look carefully at what shows up after screening.
    I listed some 2008 award projects here, to scrutinize for clues.
    https://www.physicsforums.com/showthread.php?t=248463
     
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