MANY-BODY DIFFUSION ALGORITHM - HARMONIC FERMIONS

A numerical implementation scheme is presented for the recently develo ped many-body diffusion approach for identical particles, in the case of harmonic potentials. The procedure is free of the sign problem, by the introduction of the appropriate absorption or reflection condition s for the walkers at the boundary of a state space. These conditions a re imposed by the permutation symmetry. The outflow of the walkers at the boundary of the state space contributes substantially to the energ y. Furthermore, the implementation of crossing-recrossing effects at a bsorbing boundaries proves indispensable to sample the antisymmetric s tates by discrete time steps.