Pseudo-gauge invariant non-equilibrium density operator

F. Becattini; C. Hoyos

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arXiv · 2507.09249

Pseudo-gauge invariant non-equilibrium density operator

F. Becattini·C. Hoyos

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Abstract

We obtain a form of the local thermodynamic equilibrium density operator which is invariant under pseudo-gauge transformations of the stress-energy and the spin tensors. This operator is an excellent candidate to describe the dynamics of a system which is assumed to achieve local equilibrium from a pseudo-gauge invariant quantum state, a situation which is believed to occur, for instance, in nuclear collisions at very high energy. As a consequence of pseudo-gauge invariance, the ambiguity affecting the predictions of mean values of observables from a local equilibrium state can be removed.

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F. Becattini, C. Hoyos. 2025-07-12. Pseudo-gauge invariant non-equilibrium density operator. https://arxiv.org/abs/2507.09249

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