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arXiv · 2107.00448

Ideal spin hydrodynamics from Wigner function approach

Hao-Hao Peng·Jun-Jie Zhang·Xin-Li Sheng·Qun Wang
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Abstract

Based on the Wigner function in local equilibrium, we derive hydrodynamical quantities for a system of polarized spin-1/2 particles: the particle number current density, the energy-momentum tensor, the spin tensor, and the dipole moment tensor. Comparing with ideal hydrodynamics without spin, additional terms at first and second order in the Knudsen number $\text{Kn}$ and the average spin polarization $χ_s$ have been derived. The Wigner function can be expressed in terms of matrix-valued distributions, whose equilibrium forms are characterized by thermodynamical parameters in quantum statistics. The equations of motions for these parameters are derived by conservation laws at the leading and next-to-leading order $\text{Kn}$ and $χ_s$.

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Hao-Hao Peng, Jun-Jie Zhang, Xin-Li Sheng, Qun Wang. 2021-09-29. Ideal spin hydrodynamics from Wigner function approach. https://doi.org/10.1088/0256-307x%2F38%2F11%2F116701

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