The sign problem and the Lefschetz thimble
  Recently, we have proposed a novel approach (arxiv:1205.3996) to deal with the sign problem that hinders Monte Carlo simulations of many quantum field theories (QFTs). The approach consists in formulating the QFT on a Lefschetz thimble. In this paper we concentrate on the application to a scalar field theory with a sign problem. In particular, we review the formulation and the justification of the approach, and we also describe the Aurora Monte Carlo algorithm that we are currently testing. 
Marco Cristoforetti (ECT) and Francesco Di Renzo (Parma U. and INFN,   Parma) and Luigi Scorzato (ECT)
hep-lat