Volume scaling of Dirac eigenvalues in SU(3) lattice gauge theory with color sextet fermions

Abstract

I observe a rough volume-dependent scaling of the low eigenvalues of a chiral Dirac operator in lattice studies of SU(3) lattice gauge theory with two flavors of color sextet fermions, in its weak-coupling phase. The mean value of the ith eigenvalue scales with the simulation volume V=L^4 as <lambda_i>L^p ~zeta_i, where zeta_i is a volume-independent constant. The exponent p is about 1.4. A possible explanation for this phenomenon is that p is the leading relevant exponent associated with the fermion mass dependence of correlation functions in a theory whose zero-mass limit is conformal.