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arXiv · 2510.06226

Time-reversal positivity

Shen-Hao Xu·Zhong-Chao Wei
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Abstract

We propose a new analytical tool called time-reversal positivity. It is an analogue of the Majorana reflection positivity in time-reversal symmetric case. This new time-reversal positivity can fully explain the relationship between time-reversal symmetry and the sign-free property in quantum Monte Carlo simulations. As an application, using a cone-theoretical method, we show the ground state uniqueness for the time-reversal symmetric Hubbard model.

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Shen-Hao Xu, Zhong-Chao Wei. 2025-09-27. Time-reversal positivity. https://arxiv.org/abs/2510.06226

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