Block diagonalization - an efficient method to compute hadrons on large lattices

We compute hadron masses from Wilson fermions in the quenched approximation. By use of our recently proposed block diagonalization method we are able to extend lattice sizes from (previously) 103 x 20 to 163 x 28, using a CYBER 205 with small memory. First results, based on 360 quark propagators, look very encouraging for our method: very close to Ksub(critical), we achieve good stability of the conjugate gradient algorithm, so that errors can be kept small. We thus can compute quark propagators down to a pion mass of amsub(π) = 0.2. The resulting hadron masses at β = 6 match with the values obtained previously by Lipps et al. on a 103 x 20 lattice. We find α(β = 6) = 0.093 fm and msub(proton)/msub(rho) = 1.853(88). (orig.)