Unsolved Problems of Gravity

Of nature four fundamental forces - electromagnetism, weak and strong nuclear forces and gravitation - the latter stands out as incompletely understood. The default framework is Einstein's general theory of relativity, which describes gravitation as a warping in the geometry of space-time. It is now nearly a century old, and rival theories have mushroomed in recent years. However, gravitation is such a weak force that experiments are hard to perform, leaving plenty of scope for disagreement and speculation. Fashionable ideas include string/M theory, higher space dimensions, the so-called holographic principle and theories that break Lorentz invariance. The workshop discussed new and foreseeable tests of general relativity, some new predictions of string theory, and developments in the realm of the black hole information paradox and holography.

Participants

Eric Adelberger,
University of Washington

Abhay Ashtekar,
Penn State

Zvi Bern,
University of Califronia, Los Angeles

Cliff Burgess,
Perimeter Institute

Paul Davies,
Arizona State University

Damien Easson,
Arizona State University

Jim Hartle,
University of California, Santa Barbara

Thomas Hertog,
APC, Paris

Craig Hogan,
University of Chicago

Petr Horava,
University of California, Berkeley

Mark Kasevich,
Stanford University

Lawrence Krauss,
Arizona State University

Harsh Mathur,
Case Western Reserve University

John Ruhl,
Case Western Reserve University

Raman Sundrum,
John Hopkins University

Steven Weinberg,
University of Texas

Frank Wilczek,
Massachusetts Institute of Technology

Clifford Will,
Washington University