THE COUPLED-CLUSTER METHOD APPLIED TO THE HUBBARD-MODEL

The Coupled Cluster Method which proved to be successful in calculating ground state energies for a variety of strongly interacting systems from nuclear physics to quantum chemistry, has recently been adapted to strongly interacting spins or fermions on lattices. As a simple illustration we apply it here to the motion of a single hole in a Hubbard antiferromagnet and show that accurate results on the energy and effective mass can be obtained in a straigthforward way.