The Wolff algorithm (Modified Swendsen-Wang algorithm), is an algorithm for Monte Carlo simulation of the Ising model and Potts model in which the unit to be flipped is not a single spin (as in the heat bath or Metropolis algorithms) but a cluster of them. This cluster is defined as the set of connected spins sharing the same spin states, based on the Fortuin-Kasteleyn representation.

The Wolff algorithm is similar to the Swendsen–Wang algorithm, but different in that the former only flips one randomly chosen cluster with probability 1, while the latter flip every cluster independently with probability 1/2. It is shown numerically that flipping only one cluster decreases the autocorrelation time of the spin statistics.

, where z is the exponent associated with the critical slowing down phenomena.

References

External links

• at Netlib

• Implementation in Julia: https://github.com/cossio/SquareIsingModel.jl