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arXiv · 1812.08785

A prescription for holographic Schwinger-Keldysh contour in non-equilibrium systems

Paolo Glorioso·Michael Crossley·Hong Liu
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Abstract

We develop a prescription for computing real-time correlation functions defined on a Schwinger-Keldysh contour for non-equilibrium systems using gravity. The prescription involves a new analytic continuation procedure in a black hole geometry which can be dynamical. For a system with a slowly varying horizon, the continuation enables computation of the Schwinger-Keldysh generating functional using derivative expansion, drastically simplifying calculations. We illustrate the prescription with two-point functions for a scalar operator. We then use it to derive from gravity the recently proposed non-equilibrium effective action for diffusion.

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Paolo Glorioso, Michael Crossley, Hong Liu. 2018-12-20. A prescription for holographic Schwinger-Keldysh contour in non-equilibrium systems. https://arxiv.org/abs/1812.08785

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