We study the topological and fermionic vacuum structure of four-dimensional QCD on the lattice by means of correlators of fermionic observables and topological densities. We show the existence of strong local correlations between the topological charge density and the quark condensate, charge and chiral density. By analysis of individual gauge configurations, we visualize that instantons (antiinstantons) carry positive (negative) chirality, whereas the quark charge density fluctuates in sign within instantons.
@article{arxiv.hep-lat/9809155,
title = {Chiral condensate, quark charge and chiral density},
author = {Harald Markum and Wolfgang Sakuler and Stefan Thurner},
journal= {arXiv preprint arXiv:hep-lat/9809155},
year = {2009}
}