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arXiv · 2401.05723

Advancing real-time Yang-Mills: towards real-time observables from first principles

Kirill Boguslavski·Paul Hotzy·David I. Müller
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Abstract

The complex Langevin (CL) method shows great promise in enabling the calculation of observables for theories with complex actions. Nevertheless, real-time quantum field theories have remained largely unsolved due to the particular severity of the sign problem. In this contribution, we discuss our recent progress in applying CL to a thermal SU(2) Yang-Mills theory on a 3+1 dimensional lattice. We present our anisotropic kernel that stabilizes the CL approach for real times longer than the inverse temperature - a first for Yang-Mills theory. We provide explicit evidence of reproducing symmetries and relations among different types of propagators when the complex time path approaches the Schwinger-Keldysh contour. This method paves the way for calculating transport coefficients and other real-time observables from first principles.

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Kirill Boguslavski, Paul Hotzy, David I. Müller. 2024-01-11. Advancing real-time Yang-Mills: towards real-time observables from first principles. https://arxiv.org/abs/2401.05723

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