On the configuration space topology in general relativity

The configuration-space topology in canonical General Relativity depends on the choice of the initial data 3-manifold. If the latter is represented as a connected sum of prime 3-manifolds, the topology receives contributions from all configuration spaces associated to each individual prime factor. There are by now strong results available concerning the diffeomorphism group of prime 3-manifolds which are exploited to examine the topology of the configuration spaces in terms of their homotopy groups. We explicitly show how to obtain these for the class of homogeneous spherical primes, and communicate the results for all other known primes except the non-sufficiently large ones of infinite fundamental group.