PIRSA:17030087

Schwinger-Keldysh effective field theory

APA

Jensen, K. (2017). Schwinger-Keldysh effective field theory. Perimeter Institute. https://pirsa.org/17030087

MLA

Jensen, Kristan. Schwinger-Keldysh effective field theory. Perimeter Institute, Mar. 21, 2017, https://pirsa.org/17030087

BibTex

          @misc{ pirsa_PIRSA:17030087,
            doi = {10.48660/17030087},
            url = {https://pirsa.org/17030087},
            author = {Jensen, Kristan},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Schwinger-Keldysh effective field theory},
            publisher = {Perimeter Institute},
            year = {2017},
            month = {mar},
            note = {PIRSA:17030087 see, \url{https://pirsa.org}}
          }
          

Kristan Jensen University of Victoria

Talk number PIRSA:17030087

Abstract

The subject of quantum field theory in mixed states of quantum matter is an old and rich one. The natural setting to discuss field theory in a mixed state is the Schwinger-Keldysh formalism. The subject of this talk is the set of peculiar symmetries that arise in Schwinger-Keldysh theories, and how they may be accounted for in effective field theory. In particular, when the mixed state is thermal, the effective description is constrained by two BRST-like supercharges which, at low energies, generate an algebra akin to minimal supersymmetric quantum mechanics. If time allows, I will also discuss a sort of Schwinger-Keldysh bootstrap for effective actions on more complicated closed-time-contours, which describe the out-of-time-ordered correlation functions that diagnose early-time chaotic growth in quantum systems.