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arXiv · 2009.03940

String Perturbation Theory on the Schwinger-Keldysh Time Contour

Petr Horava·Christopher J. Mogni
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Abstract

We perform the large-$N$ expansion in the Schwinger-Keldysh formulation of non-equilibrium quantum systems with matrix degrees of freedom, and study universal features of the anticipated dual string theory. We find a rich refinement of the topological genus expansion: In the original formulation, the future time instant where the forward and backward branches of the Schwinger-Keldysh time contour meet is associated with its own worldsheet genus expansion. After the Keldysh rotation, the worldsheets decompose into a classical and quantum part.

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Petr Horava, Christopher J. Mogni. 2020-09-08. String Perturbation Theory on the Schwinger-Keldysh Time Contour. https://doi.org/10.1103/physrevlett.125.261602

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