CIRCUMVENTING THE PATHOLOGICAL BEHAVIOR OF PATH-INTEGRAL MONTE-CARLO FOR SYSTEMS WITH COULOMB POTENTIALS

The imaginary-time discretized path integral for systems interacting t hrough Coulomb potentials and/or bounded by hard walls behaves patholo gically. In this paper we give an analysis of the pathologies. A new m ethod is used to calculate the path integral for the Coulomb system wi thin the primitive algorithm. This is done by constructing an effectiv e potential that implicitly depends on Trotter number P. The procedure makes possible the treatment of Coulombic potentials by means of Mont e Carlo at surprisingly low Trotter numbers and without the need of co mputing three-body potentials, necessary when high-order approximants for the density matrix are employed. (C) 1997 American Institute of Ph ysics.