Systematic covariant QG, Engle style

marcus
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This thread is in part belated appreciation of J.S.Engle's seemingly orderly systematic way of doing research, and good writing style. I'm not kidding: a clear widely understandable writing style helps a lot.

If you want a well-written review (from basics to latest) of spinfoams he has one here
http://arxiv.org/abs/arXiv:1303.4636
It's to be a chapter in Springer's Handbook of Spacetime (at press) ed Ashtekar and Petkov.

In July Engle essentially redefined LQC by establishing a symmetry reduced sector of the full LQG theory, and (significantly) doing it in a diffeomorphism invariant way. This politely pulled the rug from under an earlier somewhat over-emphatic criticism of LQC non-covariance.
Slides PDF here: http://pirsa.org/13070039
Diffeomorphism invariance and dynamic symmetry reduction
Video starts at minute 83:00 of http://pirsa.org/displayFlash.php?id=13070039

Two of Engle's students gave talks at Loops 2013
Matthew Hogan's talk starts at minute 51:00 of http://pirsa.org/13070087
Atousa Shirazi's talk starts at minute 64:00 of http://pirsa.org/13070086

By way of general introduction, here's part of what Inspire's page says.
http://inspirehep.net/author/J.S.Engle.1/
Florida Atlantic FAC 2010
U. Erlangen PD 2009 2010
CPT, Marseille PD 2009 2009
MPI, Potsdam PD 2007 2009
CPT, Marseille PD 2006 2007
Penn State U. PHD 2001 2006
Ashtekar was his PhD advisor, collaboration with Ashtekar, Rovelli, Thiemann and many others. The "E" in EPRL.

What got my attention yesterday was the Shirazi Engle paper. I think it is a major step forward in the spinfoam program: something that needed to be done. What impressed me was the orderly deliberateness (and the clear writing).
 
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It's very impressive.

Thank you for sharing this information about J.S.Engle and his work! His research and writing style is truly admirable and it is clear that he has made a significant contribution to the field of spinfoams. I am particularly impressed by his collaboration with Ashtekar, Rovelli, and Thiemann, as well as his PhD advisor Ashtekar. I am looking forward to exploring the Shirazi Engle paper to gain a better understanding of the spinfoam program and how it can be advanced.
 
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