Instanton liquid properties from lattice QCD

Abstract

We examined the instanton contribution to the QCD con gurations generated from lattice QCD for NF = 0, NF = 2 + 1 and NF = 2 + 1 + 1 dynamical quark avors from two di erent and complementary approaches. First via the use of Gradient ow, we computed instanton liquid properties using an algorithm to localize instantons in the gauge eld con gurations and studied their evolution with ow time. Then, the analysis of the running at low momenta of gluon Green's functions serves as an independent con rmation of the instanton density which can also be derived without the use of the Gradient ow.