Nonequilibrium Thermodynamical Inequivalence of Quantum Stress-energy and Spin Tensors

TL;DR

This paper demonstrates that different pseudo-gauge related stress-energy and spin tensors in quantum relativistic fields lead to distinct thermodynamic predictions, affecting transport coefficients and entropy production, thus challenging their fundamental status.

Contribution

It reveals that pseudo-gauge transformations cause thermodynamic inequivalence in quantum field stress-energy and spin tensors, impacting measurable physical quantities.

Findings

Different pseudo-gauge related tensors yield different mean values in nonequilibrium.

Transport coefficients depend on the choice of spin tensor.

Entropy production rates vary with tensor choice.

Abstract

It is shown that different pairs of stress-energy and spin tensors of quantum relativistic fields related by a pseudo-gauge transformation, i.e. differing by a divergence, imply different mean values of physical quantities in thermodynamical nonequilibrium situations. Most notably, transport coefficients and the total entropy production rate are affected by the choice of the spin tensor of the relativistic quantum field theory under consideration. Therefore, at least in principle, it should be possible to disprove a fundamental stress-energy tensor and/or to show that a fundamental spin tensor exists by means of a dissipative thermodynamical experiment.