Transport coefficients in large Nf gauge theories with massive fermions

Abstract

We compute the shear viscosity and the electrical conductivity in gauge theories with massive fermions at leading order in the large Nf expansion. The calculation is organized using the 1/Nf expansion of the 2PI effective action to next-to-leading order. We show explicitly that the calculation is gauge fixing independent and consistent with the Ward identity. We find that these transport coefficients depend in a nontrivial manner on the coupling constant and fermion mass. For large mass, both the shear viscosity and the electrical conductivity go to zero. © SISSA 2005.