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arXiv · 1901.04984

Thermalization and chaos in QED$_{3}$

Julia Steinberg·Brian Swingle
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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 initally anti-commuting fermion field operators. We compute such anti-commutators in this gauge theory to leading order in $1/N_F$. We find that the anti-commutator grows exponentially in time and compute the quantum Lyapunov exponent. We briefly comment on chaos, locality, and gauge invariance.

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Julia Steinberg, Brian Swingle. 2019-01-15. Thermalization and chaos in QED$_{3}$. https://doi.org/10.1103/physrevd.99.076007

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