Stabilising the complex Langevin method for real-time simulations of Yang-Mills theories

Abstract

The Complex Langevin (CL) method is a promising approach to overcome the sign problem, which emerges in real-time formulations of quantum field theories. Over the past decade, important stabilization techniques for CL have been developed with major applications in finite density QCD. However, they are insufficient for SU(N) gauge theories on a Schwinger-Keldysh time contour that is required for a real-time formulation. In this talk I introduce a novel anisotropic kernel that enables CL simulations on discretized time contours. Applying it to SU(2) Yang-Mills theory in 3+1 dimensions, we obtain unprecedentedly stable results that may allow us to calculate real-time observables from first principles.