Introduction To Loop Quantum Gravity

[marcus]

Atyy, thanks for asking. I did not attend Marcel XII. I think of all the conferences and workshops there have been so far this year the one I would most have enjoyed attending was the Planck Scale conference in June, in Broclaw Poland. (But the Paris Marcel XII would have been great as well.) And the one coming up that I would find most interesting is the QG Corfu School taking place in September.

Video is supposed to be posted from the Broclaw Planck Scale conference before too long:
http://www.ift.uni.wroc.pl/~planckscale/

Here is the link to the Corfu QG School
http://www.maths.nottingham.ac.uk/qg/CorfuSS.html

Another very interesting one would be the Perimeter Asymptotic Safety workshop in November:
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/
Interesting list of participants:
an Ambjorn, Utrecht University
Alfio Bonanno, INAF, Catania
Daniel Litim, University of Sussex
Max Niedermaier, University of Sussex
Martin Reuter, Mainz University
Frank Saueressig, CEA, Saclay
Lee Smolin, Perimeter Institute
B.F.L. Ward, Baylor University
Steven Weinberg, University of Texas, Austin
Jean Zinn-Justin, CEA, Saclay
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Invited_Speakers/

The Ellis-fest website has a new list of invited speakers. Some earlier invitees have apparently had to cancel due to other commitments:
Jan Ambjorn (Niels Bohr Insititute)
Martin Bojowald (Penn State)
Cliff Burgess (Perimeter)
Steve Carlip (UC Davis)
Joe Henson (Perimeter)
Renate Loll (Utrecht University)
Hermann Nicolai (Albert Einstein Institute)
Daniele Oriti (Albert Einstein Institute)
Thanu Padmanabhan (IUCAA)
Roger Penrose (Oxford)
Malcolm Perry (DAMTP)
Hanno Sahlmann (Utrecht University)
*Lenny Susskind (Stanford/Perimeter)
Kelly Stelle (Imperial)
Rafael Sorkin (Perimeter)
http://www.mth.uct.ac.za/~jeff/Quantum_Gravity/About.html

 

[marcus]

I learned how to use the Spires search more efficiently (parentheses, duh!) and so can keep track of the most-cited recent Loop and Spinfoam papers with a single search command:
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+DK+QUANTUM+GRAVITY+AND+DK+LOOP+SPACE+AND+DATE+%3E+2006+or+%28k+spin%2C+foam+and+date+%3E+2006%29&FORMAT=www&SEQUENCE=citecount%28d%29

This corresponds to typing "FIND DK QUANTUM GRAVITY AND DK LOOP SPACE AND DATE > 2006 OR (K SPIN, FOAM AND DATE > 2006)" into the Spires window, and selecting citecount order.

The last time I did this kind of survey was in March, post #150:
https://www.physicsforums.com/showthread.php?p=2104022#post2104022
and the cites for the top 20 papers ranged from 49 down to 14.
This time the top 20 papers' citecounts range from 62 down to 17.
Going from 49 to 62 is a 26% improvement, in four months.

Scanning the top 20 helps get an idea what the hot topics have been since 2006 and who the most cited authors are.

I get the same result by putting this into the window:
"( (DK QUANTUM GRAVITY AND DK LOOP SPACE) OR K SPIN, FOAM) AND DATE > 2006"
or with this in the window:
K SPIN, FOAM OR (DK QUANTUM GRAVITY AND DK LOOP SPACE) AND DATE > 2006

 

[MTd2]

Leonard Susskind, Lee Smolin, Roger Penrose and Herman Nicolain in the same conference. What do you think Marcus?

 

[marcus]

Leonard Susskind, Lee Smolin, Roger Penrose and Herman Nicolai in the same conference. What do you think Marcus?

I don't know of any upcoming conference that includes all those people as invited speakers.
A couple of posts back I listed speakers for two separate events.
One was the November AsymSafe one that included Steven Weinberg and Lee Smolin ( will also include Martin Reuter, Renate Loll and several others).

The other conference was the Ellisfest in Capetown. I think Smolin declined that one, but the speakers will include Loll, Nicolai, Penrose, Susskind...

Here is more information:
https://www.physicsforums.com/showthread.php?p=2274724#post2274724

Loll's website says she will be participating in the AsymSafe conference at Perimeter. I think that one will be interesting and quiter possibly productive. I admire and respect George Ellis, but do not expect great things from the Ellisfest. We'll see.

 

[MTd2]

I think Smolin declined that one, but the speakers will include Loll, Nicolai, Penrose, Susskind...

Yes, sorry, didnt pay attention. That's why susskind will be there, Smolin won't go.

 

[marcus]

MTd2, thanks for reminding us about the Loops 2009 conference that starts about one week from now in Beijing! In another thread you gave the current link to the main conference page:
http://www.mighty-security.com/loop/index.htm
(I imagine that the earlier website was hacked and so they were obliged to move the site to "mighty-security.com".)

Maybe we can learn something about the current state of Loop/Spinfoam research from looking at this conference.

I note right away that Loops 2009 is highly unusual in one respect: previous Loops conferences have had plenary speakers from outside the immediate Loops community:

Loops 2005 Potsdam had Robbert Dijkgraaf (string), Renate Loll (CDTriangulations), Martin Reuter (AsymSafe), and Roy Maartens (mainstream obs. cosmology). In each conference there are only a limited number of plenary talk slots so they are very precious, it is remarkable that the Potsdam organizers (Hermann Nicolai, Abhay Ashtekar and friends) gave four plenary slots away to outside Loop. I think that openness has paid off enormously to the community.

Loops 2007 Morelia had Ambjorn (CDTriangulations) and Reuter (AsymSafe). There was an unintended time-conflict with Strings 2007 Madrid so they could not get anybody good to give a string talk, but they tried. The did the best they could under the circumstances.

Loops 2008 (aka QG² 2008 Nottingham) carried on the openness tradition with several plenary speakers discussing CDTriangulations, AsymSafe, and one String speaker named Maloney (a former co-author with Witten now at U Toronto). If I remember right there were also CausalSets and or Graphity speakers. And most notably NonCommutativeGeometry was represented! Even Connes main collaborator Chamseddine was plenary speaker. So last year was very inclusive.

So the Loops conference has the tradition of being inclusive of all the major nonstring QG programs, and also some openness to String talks.

Now this year it is different. Loops 2009 Beijing is exclusively drawing from Loop/Spinfoam research. Maybe this is good to happen now and then, just for variety, but I hope it is not going to be a permanent change. I think that the Planck Scale conference in June that we have seen turned out to be an important landmark precisely because it brought people from a number of programs together to talk to each other and question each other.
=====================

The brief Preparatory School before the conference does include a series of lectures by Ruth Williams on Regge Calculus.
Here is the Prep School description:
==quote from the Prep School page==
Topics:
Loop quantum gravity, Loop quantum cosmology, Spin foams, Group field theory, Regge calculus

Lecturers:
Martin Bojowald (Penn State, USA)
Daniele Oriti (AEI, Germany)
Carlo Rovelli (Univ of Mediterranee, France)
Thomas Thiemann (AEI, Germany)
Ruth Williams (Cambridge Univ, UK)
==endquote==

Now for the main Loops 2009 conference, I estimate that the number of participants will be about 230. There are 6 pages and about 40 names on each page.
Let's look at the list of Plenary Speakers:
http://www.mighty-security.com/loop/plenary.htm
A.Ashtekar (Penn state)
J.Engle (CPT, Marseille)
M.Bojowald (Penn state)
A.Corichi (Morelia)
B. Dittich (Utrecht)
L.Freidel (Perimeter)
H.Y.Guo (ITP, CAS)
J.Lewandowski (Warsaw)
R.Maartens (Portsmounth)
J.Pullin (Louisiana)
V.Rivasseau (Paris-Sud XI)
C.Rovelli (Marseille)
H.Sahlmann (Karlsrahe)
P.Singh (Perimeter)
S.Speziale (Marseille)
T.Thiemann (AEI)
M.Varadarajan (Raman Inst)
K.Giesel(Nordita)
A.Perez(CPT, Marseille)

It does have some diversity: Roy Maartens is a top person in observational cosmology (how to test various QG theories by looking at the imprint of gravitational waves on the CMB and all kinds of early universe signals, he runs the Portsmouth center for obs. cosmo.)
And Vincent Rivasseau could be talking about Noncommutative field theory or about Renormalization stuff (loosely related to AsymSafe QG).
So it is not totally focussed on core Loop/Spinfoam research. Dittrich has a Loops background but she has recently been working on quantum Regge calculus. (That could indicate something.) Madhavan Varadarajan has worked outside but I think currently his main focus is in Loop/Spinfoam.

 

[marcus]

We now have a more complete list of the speakers at the Corfu school (13-20 September).
http://www.physics.ntua.gr/corfu2009/qg.html
Scroll down to the end.

Earlier I listed the five lecturers giving mini-course series. Rovelli, Ashtekar, Baez, Barrett, Rivasseau.
But besides these five QG minicourses there are also to be workshop talks by the following people:

* Paolo Aschieri
* Glenn Barnich
* Maja Buric
* Leonardo Castellani
* Chong-San Chu
* Brian Dolan
* Michel Dubois-Violette
* Steven Giddings
* Kristina Giesel
* Harald Grosse
* Jerzy Lewandowski
* Fedele Lizzi
* Jerzy Lukierski
* John Madore
* Shahn Majid
* Catherine Meusburger
* Denjoe O'Connor
* Martin Reuter
* Peter Schupp
* Harold Steinacker
* Richard Szabo
* Satoshi Watamura

I have highlighted a few that people here at Beyond forum may happen to recognize.
Brian Dolan I seem to recall has co-authored with John Baez, in which case he would be talking about n-category and higher gauge theory. Steve Giddings formerly did a lot of string but lately not so much. Seems to be finding other QG topics to investigate.
Martin Reuter we know would surely be talking Asymptotic Safety. He ought to be happy about the recent strong support from Steven Weinberg and AsymSafe's increased prominence. Lukierski is one of the original DSR people. Majid would talk Noncommutative Geometry, maybe also DSR. Harald Grosse and Harold Steinacker I think do noncommutative field theory. They may connect with what Rivasseau's abstract says he is going to talk about. Jerzy Lewandowski is a longtime collaborator of Ashtekar who has been a major figure in developing Loop Quantum Cosmology. Judging from his recent papers he might discuss Quantum Field Theory in Expanding Space Time.
He gave a very interesting talk about that at the Planck Scale conference in Wroclaw early July.

 

[marcus]

PDF slides are now available for some of the plenary talks given at Marcel 12 in early July.
http://www.icra.it/MG/mg12/en/
just click on plenary and select a speaker, to see if a PDF file is available.

Laurent Freidel:
http://www.icra.it/MG/mg12/talks_plenary/Freidel.pdf

Herbert Hamber:
http://www.icra.it/MG/mg12/talks_plenary/Hamber.pdf

Juan Maldacena (a string theorist, included for comparison sake)
http://www.icra.it/MG/mg12/talks_plenary/Maldacena.pdfThe Marcel Grossmann is a major international conference which is held every three years. Marcel Eleven was in Berlin 2006, Marcel Twelve was in Paris.
The theme is "recent developments in theoretical and experimental general relativity, astrophysics, and relativistic field theories." (See main page for overview and more links.)

MG12 was attended by 886 scientists:
http://www.icra.it/MG/mg12/en/participants_list.htmThe past 3 years have been an especially active period for Spin Foam and Loop QG with a wealth of new results. Freidel's talk reflects this: it is essentially a "Spin foam: current status and directions" talk. The comparison between Freidel and Maldacena's talk is revealing.

 

[MTd2]

The timetable of talks at Loop 09 is up:

http://www.mighty-security.com/loop/timetable1.htm

 

[marcus]

The timetable of talks at Loop 09 is up:

http://www.mighty-security.com/loop/timetable1.htm

Thanks for spotting that! We can get the titles of the plenary talks.

Monday 3 August
Thiemann: Loop Quantum Gravity-A Status Report
Sahlmann: The Mathematics of Canonical LQG
Giesel: Reduced Phase Space Quantization of Loop Quantum Gravity
Dittrich: Diffeomorphism Symmetry and Discreteness in Quantum Gravity

Tuesday 4 August
Ashtekar: Introduction to Loop Quantum Cosmology
Singh: On the Abscence of Singularities in Loop Quantum Cosmology
Bojowald: Loop Quantum Gravity and Cosmology
Maartens: Key Issues in Cosmology and Challenges for LQC

Wednesday 5 August
Rovelli: Loops, Foams and Scattering
Engle: Loop Quantum Gravity Spin-Foam Models
Speziale: A Geometric Quantization of SU(2) Phase Space
Evening public lecture by Rovelli: What is space? What is time? Quantum gravity and the beginning of the universe.

Thursday 6 August
Corichi: Black Holes in Loop Quantum Gravity
Perez: Black Hole Entropy and SU(2) Chern-Simon Theory
Pullin: Midi-superspace Loop Quantum Gravity
Varadarajan: Quantum Gravity and the Information Loss Problem

Friday 7 August
Oriti: Group Field Theory for Quantum Gravity
Rivasseau: Renormalization and Loop Gravity
H-Y Guo: Special Relativity Triple and Triply Special Relativity
Closing Session chaired by Ashtekar

In addition to the approximately 20 plenary session talks the titles of 72 other talks are listed to be given in the parallel sessions--two of which are being run simultaneously.

I am proud to say that 7 of the people giving papers at this conference in Beijing have been members here at PF Beyond forum. This includes three of those giving invited plenary talks---they have posted on rare occasions and/or a long time ago (one doesn't even post, just checks in and reads now and then)---and four others among those giving parallel session talks, who have posted here more often and been of considerable benefit to us.

 

[MTd2]

This is the schedule of George Ellis conference:

http://www.mth.uct.ac.za/~jeff/Quantum_Gravity/Schedule.html

 

[marcus]

Thanks! And also for posting the talks from the FQXi Azores conference that was held just a month or so ago.
I'm glad they put PDF slide sets on line, so we can check them out.
Just to have the handy, I will add it to this thread:
http://www.fqxi.org/conference/talks
Oriti's talk:
http://www.fqxi.org/data/documents/Oriti Azores Talk.pdf

I see that Daniele Oriti was in the final lineup of invited plenary talks at the Beijing conference. In fact he spoke today, 7 August. Probably essentially the same talk, giving the motivation, introduction and basics of Group Field Theory----plus its overlap (potentially as a kind of unifying framework) with Loop/Spinfoam, Simplicial (Regge) QG, CDT.

So much going on it is hard to keep proper account of it. The Planck Scale conference in Wroclaw was a really major event and now we have the Beijing, and the Marcel 12 in Paris, and the Azores conferences.
Just to keep it handy here are links for Wroclaw:
http://www.ift.uni.wroc.pl/~planckscale/movie/
Someone just asked me about the subject of Oriti's talk---which was on Day 4 in Wroclaw, and there is a video.
That thread on the Planck Scale conference is:
https://www.physicsforums.com/showthread.php?t=325794
Also an alternative link for the videos of the lectures is at Remi Durka's website:
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php

Here, for example is Oriti's Wroclaw talk slides:
http://www.ift.uni.wroc.pl/~planckscale/lectures/4-Thursday/1-Oriti.pdf
and video:
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php?plik=http://panoramix.ift.uni.wroc.pl/~planckscale/video/Day4/4-1.flv&tytul=4.1%20Oriti

 

[marcus]

The ILQGS schedule for the Fall 2009 is now posted
http://relativity.phys.lsu.edu/ilqgs/schedulefa09.html
It is a conference-call type hookup so people participate in several parts of the world.
you download the lecture slides in advance and the speaker tells you what slide.

International LQG Seminar
Sept 8 TBA
Sept 22 Vistas from perturbative quantum gravity
Richard Woodard University of Florida
Oct 6 Aharonov-Bohm and LQG
Eugenio Bianchi SNS Pisa
Oct 20 Spin foams from loop quantum gravity perspective
Jerzy Lewandowski Warszaw University
Nov 3 Group field theory and all that
Daniele Oriti Albert Einstein Institute
Nov 17 Asymptotics of the new vertex
Frank Hellmann University of Nottingham
Dec 1 Polymer parameterized field theory
Alok Laddha Raman Research Institute

Go here to see a list of all the past seminars and who gave them:
http://relativity.phys.lsu.edu/ilqgs/
For each past seminar there is an audio file, so you can listen
and a PDF file of the speaker's slides which you can download.

To keep some links handy for reference
Corfu QG School:
http://www.physics.ntua.gr/corfu2009/qg.html
Ellisfest speakers:
http://www.mth.uct.ac.za/~jeff/Quantum_Gravity/Participants.html
PlanckScale conference video and slides:
http://www.ift.uni.wroc.pl/~planckscale/
http://www.ift.uni.wroc.pl/~planckscale/movie/
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php
Marcel Twelve (886 participants):
http://www.icra.it/MG/mg12/en/
http://www.icra.it/MG/mg12/talks_plenary/Freidel.pdf
Loops 2009 (~230 part.) schedule of talks:
http://www.mighty-security.com/loop/timetable1.htm
June school for Nonperturbative Gravity and QCD at Zakopane.
http://th-www.if.uj.edu.pl/school/2009/
http://th-www.if.uj.edu.pl/school/2009/lectures.html
Asymptotic safety conference:
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/
Abhayfest:
http://igc.psu.edu/events/abhayfest/program.shtml
GRG 19 (Mexico City 5-9 July 2010):
http://www.gr19.com/index.php

Links to check for new announcements:
http://www.maths.nottingham.ac.uk/qg/
http://grg.maths.qmul.ac.uk/hyperspace/conference/
http://grg.maths.qmul.ac.uk/hyperspace/conference/latest.html

Topcited Loop/Foam papers since 2006:
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+DK+QUANTUM+GRAVITY+AND+DK+LOOP+SPACE+AND+DATE+%3E+2006+or+%28k+spin%2C+foam+and+date+%3E+2006%29&FORMAT=www&SEQUENCE=citecount%28d%29

Rovelli's talk at Strings 2008:
Video
http://cdsweb.cern.ch/record/1121957?ln=en
Slides
http://indico.cern.ch/getFile.py/acc...s&confId=21917
2003 draft of Rovelli's book online:
http://www.cpt.univ-mrs.fr/~rovelli/book.pdf
Rovelli's chapter in Oriti's book:
http://arxiv.org/abs/gr-qc/0604045
Review of LQG as of May 2008:
http://relativity.livingreviews.org/Articles/lrr-2008-5/
Steven Weinberg's 6 July talk, main CERN link:
http://indico.cern.ch/conferenceDisplay.py?confId=57283
Weinberg video:
http://cdsweb.cern.ch/record/1188567/
To save time jump to minute 58, the last 12 minutes.

 

[marcus]

Ted Jacobson's 2007 paper on renormalization as it affects LQG:
http://arXiv.org/abs/0707.4026

 

[marcus]

more links to keep handy for reference:
Photos from the first Loops conference, at Marseille 2004
http://math.ucr.edu/home/baez/marseille/
2006 video lecture by Krasnov:
http://pirsa.org/06110041/
2006 audio+pdf talk at the ILQGS:
http://relativity.phys.lsu.edu/ilqgs/krasnov032007.pdf
http://relativity.phys.lsu.edu/ilqgs/krasnov032007.aif
2009 paper Gravity as BF theory plus potential
http://arxiv.org/abs/0907.4064
Ancillary papers
http://arxiv.org/abs/0811.3147
http://arxiv.org/abs/0812.3603
Intro to Plebanski
http://arxiv.org/abs/0904.0423
Comment by Bengtsson:
http://arxiv.org/abs/gr-qc/0703114

 

[marcus]

The programme for the Corfu QG school, listing the other talks besides the main lecture series, is now posted:
http://www.physics.ntua.gr/corfu2009/Program/3rdWeekSchool.pdf
http://www.physics.ntua.gr/corfu2009/Program/3rdWeekSchool.html

The main link for the Corfu QG school with abstracts of the five lecture series is still this:
http://www.physics.ntua.gr/corfu2009/qg.html

Check here for recordings of the EG4 talks as they become available:
http://www.emergentgravity.org/index.php?main=main_EGIV_programme.php

 

[marcus]

Next summer, 2010, there will be another QG school. This time in Mexico at Uni Morelia (which hosted the Loops 2007 conference). It will last 10 days: 23 June-3 July.
The organizers are:
Don Marolf
Abhay Ashtekar
Alejandro Corichi
Maximo Banados

More info at
http://www.physics.ucsb.edu/~pasi/
The school will be aimed at advanced PhD students and postdocs to enable them to get started in QG research.
It sounds similar to the two European QG schools funded by the European agency ESF---in Zakopane 2007 and in Corfu 2009.
But this time the corresponding USian agency NSF is getting into the act and funding the school.

Immediately the school is finished, the big GR 19 conference will commence in Mexico City. It runs 5 July thru 9 July.
http://www.gr19.com/
The international conference on General Relativity and Gravitation ("GR") is held every three years. The previous one was GR 18, held at Sydney in 2007.
Here is part of the programme of parallel sessions from the GR 19 website:

==quote==

D1 Loop Quantum Gravity and Spin Foams
Chair: Alejandro Corichi

D2 Strings, branes and M-theory
Chair: (to be announced)

D3 Causal sets, Causal dynamical triangulations, Non-commutative geometry, and other approaches to quantum gravity
Chair: Fay Dowker

D4 Quantum fields in curved space-time, semiclassical gravity, quantum gravity phenomenology, and analog models
Chair: Bill Unruh
==endquote==

 

[MTd2]

Do you know when the slides from Loops 09 will be released? I am loosing hope. Also, won't you comment about http://arxiv.org/abs/0909.0939 "Spin-Foams for All Loop Quantum Gravity". I thought it was a great paper.

 

[marcus]

Do you know when the slides from Loops 09 will be released?

No I don't! And you remember that the original website was hacked, so they had to move everything to an ultra-secure host site. To me this indicates serious unexplained web-problems, and I stopped having any expectations at all.

Let's have our discussions in another thread. This thread is convenient for links that constantly get used, to check for current developments like the Corfu School. Let's make a separate thread to comment on the Lewandowski paper, if you would like.

 

[marcus]

4D quantum gravity links to keep handy for reference:
Fall 2009 schedule for International LQG Seminar, online.
http://relativity.phys.lsu.edu/ilqgs/schedulefa09.html
Upcoming talks by Woodard, Bianchi, Lewandowski, Oriti, Hellmann...
Past ILQGS talks.
http://relativity.phys.lsu.edu/ilqgs/

September 2009 Corfu QG School:
http://www.physics.ntua.gr/corfu2009/qg.html
http://www.physics.ntua.gr/corfu2009/Program/3rdWeekSchool.html

June 2009 school for Nonperturbative Gravity and QCD at Zakopane. No online media, proceedings will be published later.
http://th-www.if.uj.edu.pl/school/2009/
http://th-www.if.uj.edu.pl/school/2009/lectures.html

June 2009 PlanckScale conference video and slides:
http://www.ift.uni.wroc.pl/~planckscale/
http://www.ift.uni.wroc.pl/~planckscale/movie/
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php

July 2009 Marcel Twelve conference in Paris (886 participants):
http://www.icra.it/MG/mg12/en/
http://www.icra.it/MG/mg12/talks_plenary/Freidel.pdf

Loops 2009 in Beijing (~230 participants)
http://www.mighty-security.com/loop/timetable1.htm

August 2009 EG4 at Vancouver
http://www.emergentgravity.org/index.php?main=main_EGIV_programme.php

November 2009 Asymptotic safety conference at Perimeter:
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/

June 2010 Americas QG school at Morelia
http://www.physics.ucsb.edu/~pasi/

July 2010 GR19 conference in Mexico City
http://www.gr19.com/index.php

Links to check for new announcements:
http://www.maths.nottingham.ac.uk/qg/
http://grg.maths.qmul.ac.uk/hyperspace/conference/
http://grg.maths.qmul.ac.uk/hyperspace/conference/latest.html

Topcited Loop/Foam papers since 2006:
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+DK+QUANTUM+GRAVITY+AND+DK+LOOP+SPACE+AND+DATE+%3E+2006+or+%28k+spin%2C+foam+and+date+%3E+2006%29&FORMAT=www&SEQUENCE=citecount%28d%29

Some classic online sources:
Rovelli's talk at Strings 2008 Video
http://cdsweb.cern.ch/record/1121957?ln=en
Slides
http://indico.cern.ch/getFile.py/acc...s&confId=21917
2003 draft of Rovelli's book online
http://www.cpt.univ-mrs.fr/~rovelli/book.pdf
Rovelli's chapter in Oriti's book
http://arxiv.org/abs/gr-qc/0604045
Review of LQG as of May 2008:
http://relativity.livingreviews.org/Articles/lrr-2008-5/
Steven Weinberg's 6 July talk, main CERN link:
http://indico.cern.ch/conferenceDisplay.py?confId=57283
Weinberg video:
http://cdsweb.cern.ch/record/1188567/
To save time jump to minute 58, the last 12 minutes.
Photos from the first Loops conference, at Marseille 2004
http://math.ucr.edu/home/baez/marseille/
Krasnov 2006 video lecture (because he takes a radical longshot.)
http://pirsa.org/06110041/
Krasnov 2006 audio+pdf talk at the ILQGS
http://relativity.phys.lsu.edu/ilqgs/krasnov032007.pdf
http://relativity.phys.lsu.edu/ilqgs/krasnov032007.aif
2009 paper Gravity as BF theory plus potential
http://arxiv.org/abs/0907.4064
http://arxiv.org/abs/0811.3147
http://arxiv.org/abs/0812.3603
http://arxiv.org/abs/0904.0423
Comment by Bengtsson:
http://arxiv.org/abs/gr-qc/0703114

 

[MTd2]

http://www.perimeterinstitute.ca/en/Events/Gravity_at_a_Lifgarbagez_Point/Gravity_at_a_Lifgarbagez_Point/

Gravity at a Lifgarbagez Point

November 8 - 10, 2009
Perimeter Institute

The construction of a quantum theory of gravity might require us to give up one or more of the fundamental principles of standard quantum field theory. A recent proposal dispensing with Lorentz invariance builds upon an analogy with condensed matter systems characterized by a Lifgarbagez point. This proposal also seems to produce a theory which is well behaved in the ultraviolet regime.

This workshop intends to bring together researchers working on this or related ideas. The focus will be on the viability of the proposal (compatibility with large scale phenomenology and renormalizabilty) and its relation to other research directions, like causal dynamical triangulations and aether theories.

Scientific Organizers:
Dario Benedetti, Perimeter Institute
Robert Myers, Perimeter Institute
Petr Horava, University of California, Berkeley

******

Since the 1st day of this workshop will be in the last day of the Assymptotic Safety conference, maybe Weiberg will meet Horava, and something great will come out of that!

 

[marcus]

Another valuable resource is this collection of slides+audio from the summer 2009 Abhayfest
(celebrating the birthday of Abhay Ashtekar)
http://gravity.psu.edu/events/abhayfest/proceedings.shtml

Slides and audio available for talks by
Jim Hartle
Carlo Rovelli
Jerzy Lewandowski
Laurent Freidel
Lee Smolin
Gary Horowitz
Rodolfo Gambini
Robert Wald
Thomas Thiemann
Roger Penrose
Klaus Fredenhagen
(in no special order) and a bunch more.

 

[marcus]

Resources for conformal symmetry:
https://www.physicsforums.com/showthread.php?t=172461
(Sam Alkhaiat tutorial)
http://en.wikipedia.org/wiki/Conformal_symmetry
(very brief Wiki article with a picture)

Reflections on spontaneous symmetry breaking by Steven Weinberg
http://cerncourier.com/cws/article/cern/32522

't Hooft Erice talk (September 2009) quantum gravity should incorporate conformal symmetry in some fashion
http://arxiv.org/abs/0909.3426

Nicolai Planck Scale talk (July 2009) quantum gravity should incorporate conformal symmetry at least in the limit (and should learn certain other things from QFT and the Standard Model)
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php?plik=http://panoramix.ift.uni.wroc.pl/~planckscale/video/Day1/1-3.flv&tytul=1.3%20Nicolai

Brief Wikipedia article relating to Coleman Weinberg mechanism by which masses can be generated. C-W symmetry breaking invoked in the Meissner Nicolai extension of the Standard Model.
http://en.wikipedia.org/wiki/Coleman–Weinberg_potential

 

[marcus]

MTd2 found how to get the videos of the talks at Loops 2009, the big Loops conference at Beijing this summer.
You go to this catalog
http://www.mighty-security.com/loop/resource.htm
and you copy down the item number of the talk you want
and go to another site and request that number.

For example to get Ashtekar's talk, get the plenary session video for August 4 (8-4)
For Rovelli's, the plenary session for August 5.

Looking at the catalog, this means for Ashtekar it is serial number
8953789510079792

For Rovelli it would be
8605657721191707

For, say, Dan Oriti talking about Group Field Theory, it would be the August 7 plenary session
5570901362601769
==========================
Now suppose the video file can't be handled or there is some computer problem, they also have audio-only
And in that case the serial numbers for the same three plenary sessions are
8350111663470163
1930906596035020
1769207291471637

Let's hope some of these work. I'm going to give them a try.

It says: "go to http://file.mofile.com and enter the “pickup code” in the box at the top of the page."

So I'm going to mofile.com and entering the number 8605657721191707 which is the one for the Wednesday August 5 morning plenary session.

For more listings of the program timetable:
http://www.mighty-security.com/loop/timetable1.htm
http://www.mighty-security.com/loop/timetable2.htm
http://www.mighty-security.com/loop/timetable3.htm
http://www.mighty-security.com/loop/timetable4.htm
and so forth.

Well it didn't work for me! I went to mofile.com and put in the correct number 8605657721191707 in the right box
and things started to happen, but the screens were in Chinese! It wanted me to click on a button to continue but I couldn't read what I was agreeing to if I clicked. So being a cautious person, I bailed out.

Maybe it was working OK and I just should have clicked and continued. But it just wasn't "wai-gwo-ren" friendly, so I bailed. I think wai-gwo means foreign and ren means person.

Maybe someone who reads Chinese will try the mofile.com site out and give us a little coaching on how to proceed.

 

[marcus]

The Asymptotic Safety conference starts 5 November, less than 2 weeks away. It's an important landmark, perhaps a turning point. Interest in AsymSafe QG has revived some 30 years after Weinberg presented the idea at Erice (Sicily) in 1976.

Weinberg is working on it again and takes a sober cautious attitude. Not a sure bet, but deserves to be worked on. An alternative to string, as a way to arrive at unified fundamental description of the world. Also the running of constants like Newton G and the cosmo Lambda could provide natural mechanisms to explain cosmological phenomena such as inflation.
So AsymSafe has a key resonance with the currently hot field of cosmology---early universe in particular.

We might want to study the lineup of conference speakers and what they are talking about:
==excerpts from Perimeter host page, edited for compactness==

Thursday, November 5, 2009
8:30 - 9:20 AM Registration
9:20-9:30 AM Introductory Remarks
9:30 - 10:30 AM Steven Weinberg, University of Texas Prospects for Asymptotic Safety
11:00 AM – 12:00 PM Martin Reuter, Mainz University TBA
2:00 – 3:00 PM Jean Zinn-Justin, CEA, Saclay TBA
3:00 - 4:00 PM Holger Gies, ITP, Jena University Mechanisms of Asymptotic Safety
4:30 - 5:30 PM B.F.L. Ward, Baylor University Asymptotic Safety and Resummed Quantum Gravity

Friday, November 6, 2009
9:30-10:30 AM Lee Smolin, Perimeter Institute Asymptotic safety in the light of our modern understanding of quantum geometry
11:00AM – 12:00 PM Renate Loll, Utrecht University TBA
2:00 – 3:00 PM Max Niedermaier, Tours University Gravitational fixed points and asymptotic safety from perturbation theory
3:00-4:00 PM Frank Saueressig, Mainz University TBA
4:30-6:00 PM TBA
6:00PM Banquet Dinner

Saturday, November 7, 2009
9:30-10:30 AM Arkady Tseytlin, Imperial College, London Comments on UV divergences in quantum gravity
11:00AM – 12:00 PM Vincent Rivasseau, Universite Paris-Sud XI, Orsay TBA
2:00 – 3:00 PM Alfio Bonanno, INAF, Catania The mass-inflation phenomenon in the asymptotic safety scenario
3:00-4:00 PM John Joseph M. Carrasco, UCLA Perturbative cancellations in gravity theories
4:30-6:00PM TBA

Sunday, November 8, 2009
9:30 - 10:30 AM Jan Ambjorn, Utrecht University TBA
11:00AM – 12:00 PM Daniel Litim, University of Sussex TBA
2:00 PM "Gravity at a Lifgarbagez Point" workshop begins at 2:00pm
(Please note: Participants from the "Asymptotic Safety" workshop are welcome to stay for this afternoon's talks during the "Gravity at a Lifgarbagez Point" workshop.)

==endquote==
Another talk has been listed, but not yet assigned a time-slot:
Michael Scherer Friedrich-Schiller-Universität A mechanism for Asymptotic Safety of chiral Yukawa systems
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/
I have edited out much of the nonessential detail such as coffeebreaks, discussion, lunch, and room locations. I expect, since it is Perimeter, video of talks will appear online.
I note that Lee Smolin authored some of the early papers on AsymSafety, back in the 1980s, while postdoc at Princeton IAS, so it's not an unfamiliar topic for him. I'm especially curious to hear what both he and Renate Loll have to say. Also Bonanno in his talk on Saturday, because he has worked a lot on the connection between AsymSafe QG and early universe cosmology--some potentially elegant connections.

The chief organizer of the conference is Roberto Percacci
http://www.perimeterinstitute.ca/in...task=view&id=30&Itemid=72&pi=Roberto_Percacci
Often the organizer will act as host and not present a paper of his own, but will instead introduce the others. However in this case, since Percacci is one of the most active researchers and has contributed significantly to the field, one might hope that he doubles as a participant.
Percacci gave a talk at Zakopane in June 2009 which covered recent developments in AsymSafe, focusing on evidence for the UV fixed point. The PDF of his slides is here
http://th-www.if.uj.edu.pl/school/2009/lectures/percacci.pdf
He has a FAQ and bibliography on AsymSafe here
http://www.percacci.it/roberto/physics/as/
Here is the AsymSafe FAQ:
http://www.percacci.it/roberto/physics/as/faq.html

 

[marcus]

Jerzy Lewandowski has essentially codified Loop Foam gravity for us.
This had to happen, and there had to be a definitive 2009 exposition of the basics.
So far the best I know of is Jerzy's
http://arxiv.org/abs/0909.0939
Spin-Foams for All Loop Quantum Gravity
and the audio+slides version is at ILQGS
http://relativity.phys.lsu.edu/ilqgs/lewandowski102009.pdf
http://relativity.phys.lsu.edu/ilqgs/lewandowski102009.wav
http://relativity.phys.lsu.edu/ilqgs/

Something that impressed me, that may seem irrelevant, is how strongly Jerzy stressed the seminal importance of work by Michael Reisenberger done around 1994-1998. Here is a 1990 photo of MR at the Vatican Observatory
http://www34.homepage.villanova.edu...9/halpern/photos/reisenberger-leopold1990.jpg
Now Reisenberger is senior faculty at the Montevideo Instituto de Fisica. He and Rodolfo Gambini are the two top QG people at University of Montevideo.

Reisberger's 1994 paper was called Worldsheet formulations of gauge theories and gravity http://arxiv.org/abs/gr-qc/9412035 It was written while he was still at Utrecht, at Gerard 't Hooft's ITP.
His 1997 paper with Carlo Rovelli was called "Sum over Surfaces'' form of Loop Quantum Gravity http://arxiv.org/abs/gr-qc/9612035 This was written while he was at the Schrödinger Institute in Vienna, and also at Montevideo.
A 1998 paper that Jerzy says should still be studied more (still has germinal undeveloped ideas) is called On relativistic spin network vertices http://arxiv.org/abs/gr-qc/9809067

Jerzy points to these as the founding papers of the spinfoam approach, the genesis of the idea. He also acknowledges learning a lot from John Baez clear 2000 exposition, and the review paper by Perez.

Jerzy presents a development of the spinfoam concept that appears in a certain sense natural. He defines the vertex formula for the foam using an enclosing spinnetwork---without invoking terms like "10j symbol" or "15j symbol". If you accept the idea of cylinder function (basic to the uniqueness theorem of "L.O.S. & T.") then the spinnetwork idea is not ad hoc---it flows naturally from the cylinderfunctions on the space of connections. And then the spinfoam idea flows naturally from the spinnetwork idea. He avoids all disconnects between the ideas.

And he seems to be saying that he was helped to re-understand the spinfoam concept by going back to Reisenberger's initial vision of it, or his preliminary glimpse. After he has finished the development, he can derive the current spinfoam vertex formulas, such as the Engle-Livine- Pereira-Rovelli, and see how the technical numbers like the angular momentum "j" symbols arise.

Lewandowski has been a major force in making Loop-and-related physics mathematically rigorous. His long collaboration with Ashtekar, spanning many years and many papers, had this main thrust.

If the organizers of the September 2009 Corfu School eventually succeed in putting online the 5-hour series of lectures by Carlo Rovelli, this would be what I'd say was the current definitive version of Loop Foam gravity. But we don't have those lectures as online media yet. At least for time being, Jerzy's paper and talk will fill the bill.

Here's a current photo of Reisenberger, one of 9 snapshots of Theiss scientists.
http://www.theissresearch.org/scientists/
It's alphabetical so scroll down.

If anyone wants to google more information about the University of Montevideo, the official name is UDELAR universita de la republica. Montevideo is capital of Uruguay, which is a Republic, so the main Uni is the University of the Republic. Here is the Montevideo Institute of Physics page:
http://www.fisica.edu.uy/
and here's the faculty list:
http://www.fisica.edu.uy/integrantes.html

 

[atyy]

http://arxiv.org/abs/0909.0939

v1. The second paper we appreciate so much is the derivation of the new spin-foam model from the Holst action by Engle, Livine, Pereira and Rovelli [6]. Those two excellent works brought spin-foams closer to LQG. On the other hand, we regret have not considered here closer the Freidel-Krasnov model [12].

v2. The second paper we appreciate so much is the derivation of the new spin-foam model from the Holst action by Engle, Livine, Pereira and Rovelli [6]. Those two excellent works brought spin-foams closer to LQG. On the other hand, the works that should be and will be considered closer in the spirit of the current paper, are the Freidel-Krasnov model [15] (especially in the range of γ in which that model does not overlap with EPRL). Also the pioneering works of Reisenberger [2, 11, 13] contain a lot of ideas that still have not been explored enough in the literature.

v2 is much better (sociologically for me) - I am quite suspicious of Rovelli unless Freidel or Reisenberger are coauthors.

 

[marcus]

The Asymptotic Safety conference starts 5 November, just a few days from now. Interest in AsymSafe QG has revived some 30 years after Weinberg presented the idea at Erice (Sicily) in 1976.

A more complete list conference speakers and topics is now available:
==excerpts from Perimeter host page, edited for compactness==

Thursday, November 5, 2009
8:30 - 9:20 AM Registration
9:20-9:30 AM Introductory Remarks
9:30 - 10:30 AM Steven Weinberg, University of Texas Prospects for Asymptotic Safety
11:00 AM – 12:00 PM Martin Reuter, Mainz University Gravitational average action and asymptotic safety: past and future
2:00 – 3:00 PM Jean Zinn-Justin, CEA, Saclay Asymptotic safety: a review
3:00 - 4:00 PM Holger Gies, ITP, Jena University Mechanisms of Asymptotic Safety
4:30 - 5:30 PM B.F.L. Ward, Baylor University Asymptotic Safety and Resummed Quantum Gravity

Friday, November 6, 2009
9:30-10:30 AM Lee Smolin, Perimeter Institute Asymptotic safety in the light of our modern understanding of quantum geometry
11:00AM – 12:00 PM Renate Loll, Utrecht University TBA
2:00 – 3:00 PM Max Niedermaier, Tours University Gravitational fixed points and asymptotic safety from perturbation theory
3:00-4:00 PM Frank Saueressig, Mainz University Exploring the Theory Space of Asymptotically Safe Quantum Gravity
4:30-5:00 PM Elisa Manrique, Mainz University TBA
5:00-5:30 PM Christophe Rahmede, University of Sussex TBA

Saturday, November 7, 2009
9:30-10:30 AM Arkady Tseytlin, Imperial College, London Comments on UV divergences in quantum gravity
11:00AM – 12:00 PM Vincent Rivasseau, Universite Paris-Sud XI, Orsay TBA
2:00 – 3:00 PM Alfio Bonanno, INAF, Catania The mass-inflation phenomenon in the asymptotic safety scenario
3:00-4:00 PM John Joseph M. Carrasco, UCLA Perturbative cancellations in gravity theories
4:30-5:00PM Gian Paolo Vacca, INFN, Bologna TBA
5:00-5:30PM Michael Scherer ITP, Jena University A mechanism for Asymptotic Safety of chiral Yukawa systems

Sunday, November 8, 2009
9:30 - 10:30 AM Jan Ambjorn, Utrecht University CDT and asymptotic safety
11:00AM – 12:00 PM Daniel Litim, University of Sussex TBA

2:00 PM "Gravity at a Lifgarbagez Point" workshop begins at 2:00pm
(Please note: Participants from the "Asymptotic Safety" workshop are welcome to stay for this afternoon's talks during the "Gravity at a Lifgarbagez Point" workshop.)

==endquote==

http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/
I have edited out nonessential detail such as coffeebreaks, discussion sessions, meals, and room locations. Since it is Perimeter, video of talks might appear online.The chief organizer of the conference is Roberto Percacci
http://www.perimeterinstitute.ca/in...task=view&id=30&Itemid=72&pi=Roberto_Percacci
Percacci gave a talk at Zakopane in June 2009 which covered recent developments in AsymSafe, focusing on evidence for the UV fixed point. The PDF of his slides is here
http://th-www.if.uj.edu.pl/school/2009/lectures/percacci.pdf
He has a FAQ and bibliography on AsymSafe here
http://www.percacci.it/roberto/physics/as/
Here is the AsymSafe FAQ:
http://www.percacci.it/roberto/physics/as/faq.html

 

[marcus]

The AsymSafe conference starts tomorrow. Some new titles of talks have been added to the list, and some of the speakers have posted abstracts. Smolin's was interesting, I thought. I'm curious to know what Rivasseau is proposing as a mechanism that could underlie and cause Asymptotic Safety.

I have highlighted Rahmede's talk because he is reporting joint work with Roberto Percacci and others. The corresponding papers have just been posted on arxiv. It is possible that Rahmede's talk will cover among the most valuable recent results reported at the conference. So I highlighted those three.

Here's an updated list that includes abstracts of some talks:

Jan Ambjorn, Utrecht University
CDT and asymptotic safety
CDT is a lattice regularization of quantum gravity. The phase structure of the lattice theory is discussed and a candidate UV fixed point located.

Alfio Bonanno, INAF, Catania
The mass-inflation phenomenon in the asymptotic safety scenario

John Joseph M. Carrasco, UCLA
Perturbative cancellations in gravity theories
I will present recent results through four loops demonstrating that the maximally supersymmetric (N=8) generalization of gravity is surprisingly well behaved in the ultraviolet as a result of unexpected cancellations between contributing terms. These cancellations first manifest at one loop in the form of the "no-triangle property," with all-loop order implications through unitarity. I will conclude by discussing similar novel cancelations identified in pure Einstein gravity, at one loop, which suggest a possible explanation for the unexpectedly tame high energy behavior of N=8 supergravity beyond the limited UV protection of supersymmetry.

Holger Gies, ITP, Jena University
Mechanisms of Asymptotic Safety

Renate Loll, Utrecht University
Nonperturbative Insights from Causal Dynamical Triangulations

Max Niedermaier, Tours University
Gravitational fixed points and asymptotic safety from perturbation theory

Christoph Rahmede, Jena University
Renormalization Group Flow in Scalar-Tensor Theories

Martin Reuter, Mainz University
Gravitational average action and asymptotic safety: past and future

Vincent Rivasseau, Université Paris-Sud XI, Orsay
A New Mechanism for Asymptotic Safeness

Frank Saueressig, Mainz University
Exploring the Theory Space of Asymptotically Safe Quantum Gravity

Michael Scherer, ITP, Jena University
A mechanism for Asymptotic Safety of chiral Yukawa systems
We will discuss Weinberg's idea of asymptotic safety for a chiral Yukawa system with a U(N_L)_L x U(1)_R symmetry in a leading-order derivative expansion using nonperturbative functional RG equations. As a toy model sharing important features with the standard model we explicitely discuss N_L=10 for which we find a non-Gaussian fixed point and compute its critical exponents. We observe a reduced hierarchy problem and obtain predictions for the toy Higgs and the toy top mass.

Lee Smolin, Perimeter Institute
Asymptotic safety and deformed symmetry
I review work on asymptotic safety in quantum gravity in a 1/N expansion. I highlight the result that the scaling behavior governed by the non-trivial fixed point must be characterized by a scaling dimension less than four. Otherwise a Weyl curvature squared counterterm is required, that renders the theory unstable. This reduced scaling dimension then implies that Lorentz invariance is either broken or deformed, and this is transmitted to the matter sector. However, there are strong constraints on breaking of Lorentz invariance at the Planck scale due to the absence of birefringence of photons. The present constraints on deforming Lorentz invariance are, however, just at the Planck scale. I will then review semiclassical quantum gravity arguments that Lorentz symmetry is deformed.


Arkady Tseytlin, Imperial College, London
Comments on UV divergences in quantum gravity

Gian Paolo Vacca, Bologna University
Quantum Gravitational Corrections to Matter: A Running Controversy

B.F.L. Ward, Baylor University
Asymptotic Safety and Resummed Quantum Gravity
In Weinberg’s asymptotic safety approach to quantum gravity, one has a finite dimensional critical surface for a UV stable fixed point to generate a theory of quantum gravity with a finite number of physical parameters. The task is to demonstrate how this fixed point behavior actually arises. We argue that, in a recently formulated extension of Feynman’s original formulation of the theory, which we have called resummed quantum gravity, we recover this fixed-point UV behavior from an exact re-arrangement of the respective perturbative series. We argue that the results we obtain are consistent both with the exact field space Wilsonian renormalization group results of Reuter and Bonanno and with recent Hopf-algebraic Dyson-Schwinger renormalization theory results of Kreimer. We calculate the first "first principles" predictions of the respective dimensionless gravitational and cosmological constants and argue that they support the Planck scale cosmology advocated by Bonanno and Reuter as well. Comments on the prospects for actually predicting the currently observed value of the cosmological constant are also given.

Steven Weinberg, University of Texas, Austin
Prospects for Asymptotic Safety

Omar Zanusso, SISSA
Asymptotic safety in the nonlinear sigma models and gravity

Jean Zinn-Justin, CEA, Saclay
Asymptotic safety: a review
I shall review on field theory examples, the meaning of the concept of asymptotic safety in the context of low energy effective field theories.

---from the webpage http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Abstracts/

 

[MTd2]

BTW, have you noticed what means to Carrasco go to this conference?

BTW, let me guess, the paper in which Vincent Rivasseau will base his talk is this one:
http://arxiv.org/abs/0906.5477

 

[MTd2]

Horava Gravity conference starts in the same day Asymptotic Safety ends:

http://www.perimeterinstitute.ca/en/Events/Gravity_at_a_Lifgarbagez_Point/Gravity_at_a_Lifgarbagez_Point/

 

[atyy]

BTW, have you noticed what means to Carrasco go to this conference?

Yes, I'm very curious whether his results are at all related to AS. Gping by Percacci's GraviGUT, maybe we can soon have an AS landscape too.

 

[MTd2]

BTW, time to include this guy, B.F.L Ward, on the thread of Rovelli's program:

Resumed gravity:

http://arxiv.org/find/gr-qc/1/au:+Ward_B/0/1/0/all/0/1

I didn't know this guy, but I got hints of this idea in other papers, and posted it here

https://www.physicsforums.com/showpost.php?p=2416009&postcount=20

"[...]it is not just the physicists' trying to dig something out of diagrams. It is the couplings of the theory dynamically cooperating and organizing somehow among themselves to find a point stable in a surface, all this which ends up causing the renormalization of the theory."

EDIT.: I guess I really did read about him, I just forgot, here's more of his papers:

http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=ea+Ward,+B+F+L

 

[marcus]

RUTA recently contributed another link to add to our list of 4D quantum gravity links to keep handy for reference.
Workshops at Ashtekar's Penn State IGC:
http://www.gravity.psu.edu/events/workshops.shtml
Past talks of the International LQG Seminar, online.
http://relativity.phys.lsu.edu/ilqgs/

September 2009 Corfu QG School (so far audio has been posted for only a small portion)
http://www.physics.ntua.gr/corfu2009/qg.html
http://www.physics.ntua.gr/corfu2009/Program/3rdWeekSchool.html

June 2009 school for Nonperturbative Gravity and QCD at Zakopane. Online media incomplete.
http://th-www.if.uj.edu.pl/school/2009/
http://th-www.if.uj.edu.pl/school/2009/lectures.html

June 2009 PlanckScale conference video and slides:
http://www.ift.uni.wroc.pl/~planckscale/
http://www.ift.uni.wroc.pl/~planckscale/movie/
http://www.ift.uni.wroc.pl/~rdurka/planckscale/index-video.php

July 2009 Marcel Twelve conference in Paris (886 participants):
http://www.icra.it/MG/mg12/en/
http://www.icra.it/MG/mg12/talks_plenary/Freidel.pdf

Loops 2009 in Beijing (~230 participants)
http://www.mighty-security.com/loop/timetable1.htm

August 2009 EG4 at Vancouver. No online media so far.
http://www.emergentgravity.org/index.php?main=main_EGIV_programme.php

November 2009 Asymptotic safety conference at Perimeter:
http://www.perimeterinstitute.ca/en/Events/Asymptotic_Safety/Asymptotic_Safety_-_30_Years_Later/
AsymSafe videos:
http://pirsa.org/C09025
November 2009 Horava gravity videos:
http://pirsa.org/C09026

June 2010 Americas QG school at Morelia
http://www.physics.ucsb.edu/~pasi/

July 2010 GR19 conference in Mexico City
http://www.gr19.com/index.php

Links to check for new announcements:
http://www.maths.nottingham.ac.uk/qg/
http://grg.maths.qmul.ac.uk/hyperspace/conference/
http://grg.maths.qmul.ac.uk/hyperspace/conference/latest.html

Topcited Loop papers after 2006 (keywords SPIN FOAM, GROUP FIELD THEORY, LOOP QUANTUM COSMOLOGY, LOOP QUANTUM GRAVITY):
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+K+SPIN%2CFOAM+OR+DK+FIELD+THEORY%2C+GROUP+OR+DK+QUANTUM+GRAVITY%2C+LOOP+SPACE+OR+QUANTUM+COSMOLOGY%2C+LOOP+SPACE+AND+DATE+%3E+2006&FORMAT=www&SEQUENCE=citecount%28d%29

Some classic online sources:
Rovelli's talk at Strings 2008 Video
http://cdsweb.cern.ch/record/1121957?ln=en
Slides
http://indico.cern.ch/getFile.py/acc...s&confId=21917
2003 draft of Rovelli's book online
http://www.cpt.univ-mrs.fr/~rovelli/book.pdf
Rovelli's chapter in Oriti's book
http://arxiv.org/abs/gr-qc/0604045
Review of LQG as of May 2008:
http://relativity.livingreviews.org/Articles/lrr-2008-5/
Steven Weinberg's 6 July talk, main CERN link:
http://indico.cern.ch/conferenceDisplay.py?confId=57283
Weinberg video:
http://cdsweb.cern.ch/record/1188567/
To save time jump to minute 58, the last 12 minutes.
Photos from the first Loops conference, at Marseille 2004
http://math.ucr.edu/home/baez/marseille/
Longshots:
Vincent Rivasseau at the 2009 Perimeter AsymSafe conference.
http://pirsa.org/09110049/
Ted Jacobson at the 2009 Perimeter HorGrav conference.
http://pirsa.org/09110066/
Krasnov 2006 video lecture
http://pirsa.org/06110041/
Krasnov 2008 audio+pdf talk at the ILQGS
http://relativity.phys.lsu.edu/ilqgs/krasnov020508.pdf
http://relativity.phys.lsu.edu/ilqgs/krasnov020508.aif

 

[marcus]

The list of upcoming conferences known as "hyperspace" has moved.
http://hyperspace.aei.mpg.de/category/Conferences/