Phases and Symmetry Breaking in the Dissipative SYK Model via the Keldysh Formalism

3 Jul 2026, 10:00
30m
MR3

MR3

Department of Applied Mathematics and Theoretical Physics Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA United Kingdom
Contributed talk

Speaker

Amaury Jean (University of Cambridge)

Description

The dissipative Sachdev-Ye-Kitaev (SYK) model has recently emerged as a paradigmatic toy model of strongly interacting open quantum systems coupled to a Markovian bath, whose dynamics is governed by a Lindblad master equation. The Keldysh double-contour technique allows for analytical progress in the limit of a large number of fermion flavours, by mapping the path integral of the open SYK model to that of two coupled non-Hermitian SYK systems, where thermal phase transitions between black hole and wormhole phases have been identified. While dynamical phase transitions between such phases were previously studied, a systematic investigation of the possible phases and their symmetry properties remained unexplored. Here, we address this problem by solving the Schwinger–Dyson equations derived from the Keldysh path integral across all possible symmetry sectors, thus clarifying the nature of these phases and the patterns of symmetry breaking that underpin relaxation dynamics.

Authors

Amaury Jean (University of Cambridge) Prof. Benjamin Béri (University of Cambridge) Dr Lucas Sá (University of Cambridge)

Presentation materials