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arXiv · 2410.10602

Records from the S-Matrix Marathon: Schwinger-Keldysh Formalism

Felix M. Haehl·Mukund Rangamani
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Abstract

These notes provide an overview of real-time techniques in quantum field theories and holography. We outline the general rationale and principles underlying the Schwinger-Keldysh formalism and its out-of-time-order generalizations. To illustrate its broad utility we frame our discussion in the language of open quantum dynamics. As a specific application we describe how such real-time observables help in understanding scrambling dynamics. We also describe the holographic prescription for computing thermal Schwinger-Keldysh observables. These notes are based on a series of lectures held during the S-Matrix Marathon workshop at the Institute for Advanced Study on 11-22 March 2024.

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Felix M. Haehl, Mukund Rangamani. 2024-10-14. Records from the S-Matrix Marathon: Schwinger-Keldysh Formalism. https://arxiv.org/abs/2410.10602

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