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arXiv:1901.04984 · Physical review. D/Physical review. D.

Thermalization and chaos in QED3

Julia Steinberg, Brian G. Swingle

Published Apr 11, 2019• 26 citations
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Abstract

We study the real time dynamics of ${N}_{f}$ flavors of fermions coupled to a $U(1)$ gauge field in $2+1$ dimensions to leading order in a $1/{N}_{f}$ expansion. For large enough ${N}_{f}$, this is an interacting conformal field theory and describes the low energy properties of the Dirac spin liquid. We focus on thermalization and the onset of many-body quantum chaos which can be diagnosed from the growth of initially anticommuting fermion field operators. We compute such anticommutators in this gauge theory to leading order in $1/{N}_{f}$. We find that the anticommutator grows exponentially in time and compute the quantum Lyapunov exponent. We briefly comment on chaos, locality, and gauge invariance.

DOI
10.1103/physrevd.99.076007

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