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arXiv · 2206.09633

Page curve and symmetries

Pak Hang Chris Lau·Toshifumi Noumi·Yuhei Takii·Kotaro Tamaoka
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Abstract

Motivated by the quantum process of black hole evaporation and its implications for symmetries, we consider a qubit system with a random dynamics as a toy model of black hole. We compute its symmetry-resolved entropies and discuss its implications. We first consider the case where charges are conserved and compute the symmetry-resolved entropies. We derive a symmetry-resolved analogue of the Page curve. We then consider the case where symmetry is explicitly broken and charges are no longer conserved. It serves as a toy model for global symmetry breaking in black hole evaporation. Despite the simple framework, the symmetry-resolved entropies capture various interesting features during the analogous process of black hole evaporation in our qubit model.

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Pak Hang Chris Lau, Toshifumi Noumi, Yuhei Takii, Kotaro Tamaoka. 2022-06-20. Page curve and symmetries. https://doi.org/10.1007/jhep10(2022)015

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