Hi there, The first time I heard about chemical potential is statistical mechanics but I didn't understand that so well due to the misleading term "chemical". Recently, I am reading some introduction articles on optical lattices for bosons and it again mentions there a chemical potential for each lattice site for bosons sitting on that site. I wonder what's chemical potential is really about? What happens if it increases or decreases? What's difference for big chemical potential and small one? Thanks.