Langevin Simulations of QCD, Including Fermions

Abstract

Perhaps the first question to ask is, “Why Langevin simulations?” One way of answering this question is to examine a disease from which most simulation algorithms suffer. The disease is critical slow down [1], and we encounter it in updating when ξ/a →∞ and in matrix inversion (needed to include fermions) when m_qa → 0. A simulation that purports to solve QCD numerically will encounter these limits, so to face the challenge in the title of this workshop, we must cure the disease of critical slow down.