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  • Open Access

Quasinormal modes of relativistic Fokker-Planck kinetic theory

L. Gavassino

  • Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom

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Phys. Rev. D 114, 014018 – Published 8 July, 2026

DOI: https://doi.org/10.1103/6vfx-8kmm

Abstract

Employing the well-known unitary equivalence between Fokker-Planck operators and Schrödinger Hamiltonians, we compute the quasinormal-mode spectrum of ultrarelativistic kinetic theories with momentum-space diffusion. We show that the collision operator reduces to a Dirac-delta Schrödinger problem in one spatial dimension, and to a Coulomb Schrödinger operator with hydrogenic spectrum in three dimensions. A finite spatial wave number appears as a perturbation of the associated quantum potential. The hydrodynamic mode is found to obey exact Fick-type diffusion at all real wave numbers, whereas relativistic kinematics generically produces a continuous ballistic band in the nonhydrodynamic sector, a feature absent in the Newtonian regime.

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See Also

Diffusion Equation Is Compatible with Special Relativity

L. Gavassino
Phys. Rev. Lett. 137, 022302 (2026)

Article Text

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Information

Phys. Rev. D 114, 014018– Published 8 July, 2026
  • Received 10 February 2026
  • Accepted 20 April 2026
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