Multispin coding for spin glasses

Abstract
The authors present a multispin coding algorithm for the 2D+or-J spin glass model. It is a straightforward generalisation of Vichniac's Q2R Ising model (1984). In contrast to that, however, it is not strictly deterministic and energy conserving, so that no problems with ergodicity arise. Numerical results are given for the ground state reached by simulated annealing. They are in good agreement with previous results.