Speeding up the hybrid Monte Carlo algorithm for dynamical fermions

We propose a modification of the hybrid Monte Carlo algorithm that allows f or a larger step-size of the integration scheme at constant acceptance rate . The key ingredient is that the pseudo-fermion action is split into two pa rts. We test our proposal at the example of the two-dimensional lattice Sch winger model with two degenerate flavours of Wilson-fermions. (C) 2001 Publ ished by Elsevier Science B.V.