QED at a finite chemical potential

Abstract

We consider multi-flavor QED on a finite lattice at a finite chemical potential and show that the partition function only depends on the variables, $(\frac{{\mu }_i}{q_i}-\frac{{\mu }_1}{q_1})$, for $i=2,...$, where $q_i$, $i=\mathrm{1...}$ are integer valued charges of the various flavors and ${\mu }_i$, $i=\mathrm{1...}$ are the dimensional chemical potentials of the various flavors.

Comments: 9 pages, 4 figures, minor changes to match the version to appear in Physical Review D