Loops and Spinfoams

Carlo Rovelli, CNRS Marseille rovelli-at-cpt.univ-mrs.fr
The ``Loops and Spinfoams" conference was held in Luminy, Marseille, France, on May 3 to 7, 2004. Aim of the conference was to make the point on the loop approach to quantum gravity.

Participation has been much higher than expected: more than a hundred participant, including a large number of young researchers and students. Discussion has been intense and the atmosphere friendly and very lively.

The conference was articulated in thematic days, focused on: (i) Canonical loop quantum gravity, (ii) the spinfoam formalism, (iii) applications, and (iv) related approaches. The program was developed in 45 presentations of different lengths, too many for illustrating them here individually. Very ample time was left for questions and for discussion, a format that has proven effective and has been appreciated by the participants.

The overall picture of the research in nonperturbative quantum gravity that has emerged is encouraging. The loop approach, with its rich variety of versions and formalisms, is still incomplete, and a large number of issues remain open. But there is a large common ground in the variety of points of view. A general understanding on how to formulate background independent quantum field theory exists and yields to a credible hypothesis of solution to the quantum gravity puzzle. In addition, loop quantum gravity is finding an increasing spectrum of applications.

A general discussion during the last morning has been based on a list of questions proposed by the audience. The list of these questions (quite interesting, and requested by many) can be found from my home page http://www.cpt.univ-mrs.fr/~rovelli. Pictures of the conference can be found in http://perimeterinstitute.ca/activities/scientific/cws/marseille.cfm. Publication of proceedings has been suggested and is being considered.

The weather, uncharacteristically grey during the first days, has cleared up for the free afternoon, allowing the participants to spread along the sea and in the marvelous wilderness of Marseille's ``Calanques".

Jorge Pullin 2004-09-10