TEMPERATURE EXPANSIONS FOR MAGNETIC SYSTEMS

We derive finite temperature expansions for relativistic fermion syste ms in the presence of background magnetic fields, and with nonzero che mical potential. We use the imaginary-time formalism for the finite te mperature effects, the proper-time method for the background field eff ects, and zeta function regularization for developing the expansions. We emphasize the essential difference between even and odd dimensions, focusing on 2 + 1 and 3 + 1 dimensions. We concentrate on the high te mperature limit, but we also discuss the T = 0 limit with nonzero chem ical potential. (C) 1996 Academic Press, Inc.