This is a program which demonstrates the 2-D Ising Magnet, a very
useful model in chemistry, physics, and many other sciences, even the
social "sciences". The model consists of a grid of "magnets" which can
be either up or down. The magnetic poles interact only with their four
nearest neighbors, and there is a certain energy penalty for
misaligning two neighboring poles.
Depending on the "temperature" (the amount of random energy available
for flipping poles), the magnet may be random, or it may demonstrate
short or long range correlations in orientation. There is a critical
temperature at about 2.3 below which the magnet freezes.
