The problems in gravitational physics to be studied can be presented under six headings: classical gravity and cosmology, quantum cosmology, technical issues relevant to quantization of gravity, spin and statistics of quantum particles, dynamical change of spacetime topology, and a discrete model for spacetime. These address very fundamental aspects of gravitation theory. More specifically, the investigators will study: gravitational conservation laws, "topological cosmic censorship," properties of exponentially expanding universes; consequences of using elapsed 4-volume as a time-parameter for quantum cosmology; the implications of coordinate and gauge invariance for different quantization schemes, formulation of the Einstein equations on light-like hyper-surfaces as well as at large spatial distances; a possible topological proof of the spin-statistics correlation, and its implications for quantum gravity; field fluctuations in spacetimes whose topology changes, the splitting off from our universe of regions of non- trivial topology; and the possibility of adopting a discrete model for spacetime in which the basic relation is a partial order, the reformulation of topological and metrical notions in this framework, and the subsequent search for a classical limit.
