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arXiv · 1807.02071

General thermodynamic equilibrium with axial chemical potential for the free Dirac field

M. Buzzegoli·F. Becattini
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Abstract

We calculate the constitutive equations of the stress-energy tensor and the currents of the free massless Dirac field at thermodynamic equilibrium with acceleration and rotation and a conserved axial charge by using the density operator approach. We carry out an expansion in thermal vorticity to the second order with finite axial chemical potential $\mu_A$. The obtained coefficients of the expansion are expressed as correlators of angular momenta and boost operators with the currents. We confirm previous observations that the axial chemical potential induces non-vanishing components of the stress-energy tensor at first order in thermal vorticity due to breaking of parity invariance of the density operator with $\mu_A \ne 0$. The appearance of these components might play an important role in chiral hydrodynamics.

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M. Buzzegoli, F. Becattini. 2018-07-05. General thermodynamic equilibrium with axial chemical potential for the free Dirac field. https://doi.org/10.1007/jhep12(2018)002

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