ITP Conference on strong gravitational fields

Don Marolf, Syracuse University

The ITP Conference on Strong Gravitational Fields (Santa Barbara, CA, June 22-26, 1999) was the culminating event of the six month ITP program ``Classical and Quantum Physics of Strong Gravitational Fields.'' The intent of the conference was to focus on those aspects of strong gravitational fields that had been emphasized in the six month program, but to extend the audience far beyond the program participants.

One of the most unusual aspects of the conference was the basic organization. This was to be a ``Discussion Conference.'' The schedule featured a relatively small number of invited talks, each of which was followed by 40 minutes of discussion time. This time allowed time for both an in depth conversation between speaker and audience (and often among the audience members) as well as for short presentations by various participants on topics related to the main talk. I think that everyone was impressed at just how well this format seemed to work and the extend to which the discussions clarified and brought forth important issues from the talks. I was especially told by the less experienced participants that this format allowed them to see more clearly what were the important parts of a given talk. The conference also featured a few (14) contributed presentations, and a panel discussion (Bob Wald, Jürgen Ehlers, Pablo Laguna, and Beverly Berger) on classical relativity. The full audio recordings of all talks, short presentations, and ensuing discussions are available on line at the above URL.

Like the preceding ITP program, the conference had three main foci. One of these was quantum gravity, especially loop quantum gravity and string theory. Review talks on these subjects were given by Gary Horowitz, Joe Polchinski, Rob Myers, Abhay Ashtekar, John Baez, and Carlo Rovelli. Another was classical physics, including Gravitational waves (John Friedman and Eanna Flanagan) and Numerical Relativity (Richard Price and Carsten Gundlach). The third was Mathematical Relativity (Rick Shoen, Hubert Bray). I was very pleased with the degree to which all speakers gave talks that were accessible to broad audiences. As a result, the talks on line at the above URL provide an excellent place for non-specialists to get insight into topics from the recent proofs of the Penrose Inequalities to the status of black hole collision simulations, and from gravitational wave sources to microscopic black hole entropy from both the loop and string points of view. Rather than go into details here, I would strongly urge the reader to go directly to the conference URL above, view the transparencies, and listen to the talks and ensuing discussions. In a few places the audio recordings are a bit rough (due to interference from the nearby airport), but there is no doubt that they will be a useful resource.

The conference webpage is

Jorge Pullin