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arXiv · 1611.07268

Thermal pure state path integral and emergent symmetry

Shin-ichi Sasa·Sho Sugiura·Yuki Yokokura
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Abstract

We investigate a thermally isolated quantum many-body system with an external control represented by a time-dependent parameter. We formulate a path integral in terms of thermal pure states and derive an effective action for trajectories in a thermodynamic state space, where the entropy appears with its conjugate variable. In particular, for quasi-static operations, the symmetry for the uniform translation of the conjugate variable emerges in the path integral. This leads to the entropy as a Noether invariant.

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Shin-ichi Sasa, Sho Sugiura, Yuki Yokokura. 2016-11-22. Thermal pure state path integral and emergent symmetry. https://arxiv.org/abs/1611.07268

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