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arXiv · 2511.14787

Relativistic resistive magnetohydrodynamics for a two-component plasma

Khwahish Kushwah·Caio V. P. de Brito·Gabriel S Denicol
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Abstract

We derive relativistic resistive magnetohydrodynamics for a two-component ultrarelativistic plasma directly from kinetic theory. Starting with the Boltzmann--Vlasov equation and using the 14-moment approximation in the Landau frame, we obtain coupled evolution equations for the charge diffusion four-current and the shear-stress tensor. Benchmarking against the usual Israel-Stewart type relaxation form shows that this simplified description is accurate for small viscosity to entropy ($\eta/s$) ratio, vanishing magnetic field, and not so strong electric field. Outside this regime the dynamics depart in a controlled way, i.e., strong electric fields introduce nonlinear back-reaction that delays and reduces current peaks, and a sizable shear-stress is produced even without a flow profile.

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Khwahish Kushwah, Caio V. P. de Brito, Gabriel S Denicol. 2025-11-13. Relativistic resistive magnetohydrodynamics for a two-component plasma. https://doi.org/10.1103/tl97-r2kh

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