LATTICEEASY is a C++ program for doing lattice simulations of the evolution of interacting scalar fields in an expanding universe. The program is designed so that you can easily do runs with different parameters, and more importantly can easily introduce new models to evaluate. Starting with LATTICEEASY 2.0 you can do these simulations in one, two, or three dimensions simply by resetting a single variable. There is also a parallel processing version of LATTICEEASY called CLUSTEREASY.
The program is available on the Web at http://www.science.smith.edu/departments/Physics/fstaff/gfelder/latticeeasy. It is freely available to anyone who wants to use it or modify it. For details see the terms of use section; basically it says that you can do whatever you want with the program as long as you continue to give us credit and leave our contact information with it so that people can contact us about it.
If you have any questions or comments about LATTICEEASY please email us at gfelder@email.smith.edu. We would love to hear how the program is working for you, and we would be happy to help with any questions you might have, bug reports, suggestions for future improvements, or anything else you might want to tell us about the program.
This document is divided into four main sections. Using LATTICEEASY describes the use of LATTICEEASY. It tells you how to compile and run the program, how to set appropriate parameters for a given model, and finally how to create new models for the program to run. Output describes the output of the program. It lists each of the output functions in the program and describes the files they create and how to interpret their results. Equations derives and explains the equations used by the program. Much of this section isn't necessary for using the program, but is necessary for understanding what the program does and why. One of the most important parts of this section deals with the variable rescalings used by the program. In order to simplify the equations the program uses rescaled values for fields and spacetime variable, and these rescalings are derived and explained in the Equations chapter. These rescalings are used throughout the use and output chapters, so you may find that some parts of these sections make more sense after you have read the Equations chapter. Nonetheless, these first two sections contain all the information you need to get started using the program. CLUSTEREASY describes the parallel processing version of LATTICEEASY.
There are a few minor sections in addition to these major ones. Chapter 2 describes our notation and conventions. Chapter 3 lists the files in LATTICEEASY and briefly describes what each of them does. Chapter 8 gives the terms of use for the program. This ``credit'' section is also reproduced in the comments at the top of latticeeasy.cpp, the main file of the program.