Loops '05

Thomas Thiemann, Albert Einstein Institute thiemann-at-aei.mpg.de

In the Einstein year, the almost annnual conference on background independent approaches to quantum gravity took place at the Albert Einstein Institute in Potsdam, close to Berlin, Germany. The official title of the conference was `Loops 05', however, not only Loop Quantum Gravity (LQG) researchers were present but also practitioners of the other non - perturbative approaches. Plenary talks were distributed among the following topics: 1. Asymptotically Safe Quantum Gravity, 2. Causal Sets, 3. Dynamical Triangulations, 4. Generally Covariant Algebraic Quantum Field Theory and 5. Loop Quantum Gravity. Almost all the leaders in those fields were present at the conference, in particular, 1. Reuter, 2. Sorkin and Dowker, 3. Loll, 4. Verch, 5. Ashtekar, Baez, Barrett, Corichi, Freidel, Gambini, Lewandowski, Perez, Pullin, Rovelli and Smolin. There were also talks on background independent aspects of string theory (Dijkgraaf and Theisen), Supergravity (Julia), Emergent Quantum Gravity (Morales - Tecotl) and Quantum Cosmology (Maartens).

There were 20 plenary talks and 63 afternoon talks which, for the first time, had to be distributed over two parallel sessions. We had more than 150 official registrations but the lecture theater was sometimes filled close to capacity (210 seats). This was certainly the biggest quantum gravity conference focusing on background independent approaches so far. It is pleasing to observe that the number of participants at this kind of meetings is rapidly increasing. From my own memory I recall the following conferences and rough participant numbers respectively: Banach Center, Warsaw, Poland, 1995 (50); Punta Del Este, Uruguay, 1996, (40); ESI, Vienna, Austria, 1997, (60); Banach Center, Warsaw, Poland, 1997 (60); ITP, Santa Barbara, USA, 1999, (70), Banach Center, Warsaw, Poland, 2001 (60); IGPG, State College, USA, 2003 (90); CPT, Luminy, France, 2004 (110).

The conference was subsidized by the Max Planck Gesellschaft (MPG) and The Perimeter Institute for Theoretical Physics (PI). While PI sponsored the conference poster, the money from the MPG and about 60% of the conference fee (EUR150,-), which was cashed only from non - students, was solely used in order to enable students to participate. I would like to take the opportunity to thank the plenary speakers once again for not asking for reimbursement which would have down-sized the student participation by an order of 40 people.

Due to the help of the marketing company `Milde Marketing', the conference also had quite some impact on the German press. Major articles appeared for instance in the Frankfurter Allgemeine Zeitung and the television company RBB interviewed some of the participants and intends to broadcast parts of the conference. Also, Lee Smolin spoke in the `Urania', a world famous institution in Berlin, which focuses on mediating science to the public through popular talks.

The scientific contributions to the conference can be downloaded, in many cases both audio and video, from the conference website http://loops05.aei.mpg.de. It is difficult to single out particular highlights but maybe one of the lessons to take home from the conference is that all afore mentioned approaches start deriving results relevant for quantum cosmology which is very important in view of the fact that precision cosmological measurements such as WMAP and later PLANCK might be able to detect quantum gravity fingerprints in the CMB.

Personally, I would be very pleased if somebody took the energy to organize Loops06: Let us keep up the momentum and make this meeting an annual forum of our small but growing community.