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arXiv · 2107.11416

Thermalization of Gauge Theories from their Entanglement Spectrum

Niklas Mueller·Torsten V. Zache·Robert Ott
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Abstract

Using dual theories embedded into a larger unphysical Hilbert space along entanglement cuts, we study the Entanglement Structure of $\mathbf{Z}_2$ lattice gauge theory in $(2+1)$ spacetime dimensions. We demonstrate Li and Haldane's conjecture, and show consistency of the Entanglement Hamiltonian with the Bisognano-Wichmann theorem. Studying non-equilibrium dynamics after a quench, we provide an extensive description of thermalization in $\mathbf{Z}_2$ gauge theory which proceeds in a characteristic sequence: Maximization of the Schmidt rank and spreading of level repulsion at early times, self-similar evolution with scaling coefficients $\alpha = 0.8 \pm 0.2$ and $ \beta = 0.0 \pm 0.1$ at intermediate times, and finally thermal saturation of the von Neumann entropy.

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Niklas Mueller, Torsten V. Zache, Robert Ott. 2021-07-23. Thermalization of Gauge Theories from their Entanglement Spectrum. https://doi.org/10.1103/physrevlett.129.011601

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