  A numerical implementation scheme is presented for the recently developed
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 conditions for the walkers at the
boundary of a state space. These conditions are imposed by the permutation
symmetry. The outflow of the walkers at the boundary of the state space
contributes substantially to the energy. Furthermore, the implementation of
crossing/recrossing effects at absorbing boundaries proves indispensable to
sample the antisymmetric states by discrete time steps.
