Nonequilibrium Thermodynamical Inequivalence of Quantum Stress-energy and Spin Tensors

Understand

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.