An Algebraic Proof of Thermal Wick's Theorem

Ruofan Chen

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arXiv · 2501.03665

An Algebraic Proof of Thermal Wick's Theorem

Ruofan Chen

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Abstract

Every many-body state can be constructed from the vacuum state by iteratively applying the creation operators, therefore the thermal expectation can be transformed into a sum of vacuum expectation where the vacuum Wick's theorem holds. Based on this observation this article gives an algebraic proof of thermal Wick's theorem.

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Ruofan Chen. 2025-01-07. An Algebraic Proof of Thermal Wick's Theorem. https://arxiv.org/abs/2501.03665

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