THE INITIAL SINGULARITY IN SOLUTIONS OF THE EINSTEIN-VLASOV SYSTEM OFBIANCHI TYPE-I

The dynamics of solutions of the Einstein-Vlasov system with Bianchi I symmetry is discussed in the case of massive or massless particles. I t is shown that in the case of massive particles the solutions are asy mptotic to isotropic dust solutions at late times. The initial singula rity is more difficult to analyze. It is shown that the asymptotic beh avior there must be one of a small set of possibilities, but it is not clear whether all of these possibilities are realized. One solution i s exhibited in the case of massless particles, which behaves quite dif ferently near the singularity from any Bianchi I solution with perfect fluid as a matter model. In particular, the matter is not dynamically negligible near the singularity for this solution. (C) 1996 American Institute of Physics.