QG with an Orsay accent (what I got from the Perimeter AsymSafe conference)

[marcus]

For me the most exciting talk, with the most new content, was by Vincent Rivasseau.
He is at Orsay. That means the top Paris center for physics theory. We should get some slight acquaintance with the person, as well as his current research.

http://www.rivasseau.com/index.html
Born in 1955 making him now in mid-50s.
His homepage is extremely concise and free of rhetoric. He says only what is necessary. His research is described as follows:
http://www.rivasseau.com/2.html
"I am a mathematical physicist specialist of constructive quantum field theory and renormalization.

I have worked to apply this theory especially to the problem of interacting Fermions in condensed matter.

Since 2004 I study quantum field theory on noncommutative space-time and more recently the new group field theory approaches to quantum gravity."

That's all. For me what stands out is the recent focus on "the new group field theory approaches to quantum gravity".

====================

Vincent Rivasseau's talk at the Perimeter conference is here:
http://pirsa.org/09110049/

One thing I find delightful is that this is someone who has started only in the past two years to explore Spin Foam models and GFT, and in this talk he is already reinterpreting the formalism and proposing major changes in how to do things. It's refreshing to watch: encouraging, stimulating---and his suggestions being based on his experience with condensed matter and noncommutative field theory are possibly enlightening. He helps one to see things a different way.

So I got a good impression of how physics might be done at Orsay.

It appears that right now in France there are a remarkable number of strong 4d QG people---at Marseille and Orsay of course, but also other places too, like Lyon, Tours, Montpellier. It's beginning to look like a "critical mass" concentration.

 

[atyy]

Yes, I think this is very exciting. In addition to Rivasseau, some other people who have worked on renormalization of non-commutative field theories who are now doing GFT renormalization are Gurau and Tanasa.
http://arxiv.org/abs/0906.5477
http://arxiv.org/abs/0905.3772
http://arxiv.org/abs/0909.5631

The key works linking GFT to non-commutative field theory and to condensed matter:
http://arxiv.org/abs/hep-th/0512113
http://arxiv.org/abs/gr-qc/0203036

BTW, I think this has nothing to do with Asymptotic Safety, and more to do with condensed matter - Markopoulou is the author of the last link, and you can see that she was already inspired by condensed matter at that time - Quantum Graphity is cited in Rivasseau's paper, nothing to do with the substance, but as a hope for the future - so I'm sure it won't work, but very exciting nonetheless

 

[ensabah6]

Is this in anyway related to

http://arxiv.org/abs/0710.3276, and if so can you get either Wen or Volvovik's emergent SM from this?

Group field theory as the microscopic description of the quantum spacetime fluid: a new perspective on the continuum in quantum gravity
Authors: Daniele Oriti
(Submitted on 17 Oct 2007)

We introduce the group field theory (GFT) formalism for non-perturbative quantum gravity, and present it as a potential unifying framework for several other quantum gravity approaches, i.e. loop quantum gravity and simplicial quantum gravity ones. We then argue in favor of and present in detail what we believe is a new GFT perspective on the emergence of continuum spacetime from discrete quantum structures, based on the idea of quantum space as a condensed matter system. We put forward a more specific, albeit still very much tentative, proposal for the relevant phase of the GFT corresponding to the continuum: a Bose-Einstein condensate of GFT quanta. Finally, we sketch how the proposal may be realized and its effective dynamics could be extracted in the GFT setting and compared with continuum gravity theories.

 

[atyy]

Is this in anyway related to

http://arxiv.org/abs/0710.3276, and if so can you get either Wen or Volvovik's emergent SM from this?

Group field theory as the microscopic description of the quantum spacetime fluid: a new perspective on the continuum in quantum gravity
Authors: Daniele Oriti
(Submitted on 17 Oct 2007)

We introduce the group field theory (GFT) formalism for non-perturbative quantum gravity, and present it as a potential unifying framework for several other quantum gravity approaches, i.e. loop quantum gravity and simplicial quantum gravity ones. We then argue in favor of and present in detail what we believe is a new GFT perspective on the emergence of continuum spacetime from discrete quantum structures, based on the idea of quantum space as a condensed matter system. We put forward a more specific, albeit still very much tentative, proposal for the relevant phase of the GFT corresponding to the continuum: a Bose-Einstein condensate of GFT quanta. Finally, we sketch how the proposal may be realized and its effective dynamics could be extracted in the GFT setting and compared with continuum gravity theories.

See footnote 3 in http://arxiv.org/abs/0906.5477. Rank speculation of course.