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arXiv:2511.11861 · Physical Review A

Relativistic Maxwell-Bloch Equations with Applications to Astrophysics

Ningyan Fang, Victor Botez, Fereshteh Rajabi, Martin Houde

quant-phastro-ph.HEgr-qcSubmitted Nov 14, 2025• Announced Nov 18, 2025• 0 citations• Revised Apr 13, 2026 (v2)
v1 · Nov 14, 2025v2 · Apr 13, 2026
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Abstract

We derive relativistic Maxwell-Bloch equations for potential applications in astronomical environments, where various radiative processes are known to occur, including the maser action and Dicke's superradiance. We show that for both phenomena a radiating system's response is preserved at different relative velocities between the system's rest frame and the observer, while the relevant timescales and the radiation intensity transform as expected from relativistic considerations. We verify that the level of coherence between groups of emitters travelling at different speeds is unchanged in all reference frames. We also derive relativistic versions of the maser equations applicable in the steady-state regime.

Journal reference
Phys. Rev. A 113, 043711 (2026)
DOI
10.1103/3dqj-hrht
Comments
10 pages, 5 figures

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