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arXiv · 1907.10061

Extended Eigenstate Thermalization and the role of FZZT branes in the Schwarzian theory

Pranjal Nayak·Julian Sonner·Manuel Vielma
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Abstract

In this paper we provide a universal description of the behavior of the basic operators of the Schwarzian theory in pure states. When the pure states are energy eigenstates, expectation values of non-extensive operators are thermal. On the other hand, in coherent pure states, these same operators can exhibit ergodic or non-ergodic behavior, which is characterized by elliptic, parabolic or hyperbolic monodromy of an auxiliary equation; or equivalently, which coadjoint Virasoro orbit the state lies on. These results allow us to establish an extended version of the eigenstate thermalization hypothesis (ETH) in theories with a Schwarzian sector. We also elucidate the role of FZZT-type boundary conditions in the Schwarzian theory, shedding light on the physics of microstates associated with ZZ branes and FZZT branes in low dimensional holography.

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Pranjal Nayak, Julian Sonner, Manuel Vielma. 2019-07-23. Extended Eigenstate Thermalization and the role of FZZT branes in the Schwarzian theory. https://doi.org/10.1007/jhep03(2020)168

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