This is essentially the same as program 4, but with two sets of particles. The
blue dots expand from the left (L) compartment to the entire volume, and the
red dots expand from the right (R) compartment to the entire volume. This is
often referred to as a “mixing process”, but it is basically an expansion of
two different gases. Again, this program does not add any new idea that is not
contained in the expansion process simulated in program 4.