A discrete vector spin model

A modification of the classical Heisenberg model is proposed in which the continuously rotating spin variables are replaced by spins which are only allowed an isotropically distributed discrete set of directions. The change is motivated by a need to simplify the calculations associated with Monte Carlo simulation of vector spin systems, a goal accomplished by the present model. An efficient table-based simulation technique is described and preliminary results for the critical region presented: various extensions of the model are discussed.