CLUSTEREASY: A program for lattice simulations of scalar fields in an expanding universe on parallel computing clusters Original Research Article

We describe an MPI C++ program that we have written and made available for calculating the evolution of interacting scalar fields in an expanding universe on parallel clusters. The program is a parallel programming extension of the simulation program LATTICEEASY. The ability to run these simulations on parallel clusters, however, greatly extends the range of scales and times that can be simulated. The program is particularly useful for the study of reheating and thermalization after inflation. The program and its full documentation are available on the Web at . In this paper we provide a brief overview of what the program does and what it is useful for.