Monte Carlo Study of the Widom-Rowlinson Fluid Using Cluster Methods

The Widom-Rowlinson model of a fluid mixture is studied using a new cluster algorithm that is an adaptation of the invaded cluster method previously applied to Potts models. The algorithm overcomes the difficulties of treating continuum hard-core systems and has almost no critical slowing down. Our estimates of $\beta /\nu$ and $\gamma /\nu$ for the two-component fluid are consistent with the Ising universality class in two and three dimensions. We also present preliminary results for the three-component fluid.