Volume behaviour of quark condensate, pion mass and decay constant from Dyson-Schwinger equations

Jan Luecker, Christian S. Fischer, Richard Williams

Published 2009-12-18, updated 2010-05-03Version 2

We solve the coupled system of Dyson-Schwinger and Bethe-Salpeter equations for the quark propagator and the pion Bethe-Salpeter amplitude on a finite volume. To this end we use a truncation scheme that includes pion cloud effects in the quark propagator and light mesons. We study volume effects in the quark condensate, the pion mass and the pion decay constant and compare to corresponding results in other approaches. In general we find large effects for volumes below V=(1.8 fm)^4.