University of Chicago
A Symposium on ``Black Holes and Relativistic Stars'' was held on the University of Chicago campus on the weekend of December 14 and 15, 1996. The Symposium was dedicated to the memory of S. Chandrasekhar, who died in August, 1995 and had devoted much of the last 30 years of his scientific career to research in these areas. Although the Symposium was originally envisioned as a relatively ``small'' meeting, it was attended by over 500 registered participants, about half of whom came from outside of Chicago. Many of the participants stayed to attend the ``Texas Symposium'', which was held in downtown Chicago during the following week. The Symposium consisted of twelve plenary talks, each one hour in length. Valeria Ferrari opened the Symposium on Saturday morning with a review of her work, done in collaboration with Chandrasekhar, on perturbations of black holes and relativistic stars. John Friedman reviewed work on rotating relativistic stars, including the information to be gained from millisecond pulsars on neutron star matter. Kip Thorne brought us up to date on the status of LIGO and VIRGO and reviewed what we might learn from them and LISA about black holes and neutron stars. In the Saturday afternoon session, Martin Rees reviewed the observational evidence for black holes, including some new, strong evidence for black holes at the centers of galaxies. Roger Penrose presented some perspectives on cosmic censorship and singularities. Saul Teukolsky described some of the ongoing research in numerical relativity, aimed at analyzing the collisions of black holes. In the Sunday morning session, Werner Israel discussed his work and that of others on the internal structure of black holes. I reviewed the status of black hole thermodynamics, with an emphasis on the apparent ``universality'' of the laws. Rafael Sorkin then presented some of his ideas related to the statistical origin of the laws of black hole thermodynamics. The Sunday afternoon session began with James Hartle describing generalized quantum theory and how it might treat issues associated with black hole evaporation. Stephen Hawking reviewed his ideas on the loss of quantum coherence due to black holes and briefly described a new calculation related to this process. The Symposium concluded with a relatively non-technical talk by Edward Witten, which reviewed the development of ideas in string theory and gave his present perspectives on ``quantum and stringy geometry''. The proceedings of the Symposium will be published by the University of Chicago Press, and should be available in early 1998.