Topology in lattice QCD

Abstract

The status of topology on the lattice is reviewed. Recent results show that the topological susceptibility chi can be unambigously determined. Different methods, if properly implemented, give results consistent with each other. For SU(3) the Witten-Veneziano prediction is confirmed. Preliminary results for full QCD are presented. The problem there is that the usual hybrid montecarlo algorithm has severe difficulty to thermalize topology. Possible ways out are under study.