We study an infinite system of Brownian hard balls, moving in R-d and submi
tted to a smooth infinite range pair potential. It is represented by a diff
usion process, which is constructed as the unique strong solution of an inf
inite-dimensional Skorohod equation. We also prove that canonical Gibbs sta
tes associated to the sum of the hard core potential and the pair potential
are reversible measures for the dynamics. (C) 2000 Elsevier Science B.V. A
ll rights reserved.