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  • Letter
  • Open Access

Strong-field magnetohydrodynamics for neutron stars

Shreya Vardhan1,*, Sašo Grozdanov2,3,†, Samuel Leutheusser4,‡, and Hong Liu5,§

  • 1Stanford Institute for Theoretical Physics, Stanford University, Stanford, California 94305, USA
  • 2Higgs Centre for Theoretical Physics, University of Edinburgh, Edinburgh EH8 9YL, Scotland
  • 3Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, SI-1000 Ljubljana, Slovenia
  • 4Princeton Gravity Initiative, Princeton University, Princeton, New Jersey 08544, USA
  • 5Center for Theoretical Physics, MIT, Cambridge, Massachusetts 02139, USA

  • *Contact author: vardhan@stanford.edu
  • †Contact author: saso.grozdanov@ed.ac.uk
  • ‡Contact author: sl9535@princeton.edu
  • §Contact author: hong_liu@mit.edu
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Phys. Rev. Research 6, L042050 – Published 26 November, 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.L042050

Abstract

We present a formulation of magnetohydrodynamics which can be used to describe the evolution of strong magnetic fields in neutron star interiors. Our approach is based on viewing magnetohydrodynamics as a theory with a one-form global symmetry and developing an effective field theory for the hydrodynamic modes associated with this symmetry. In the regime where the local velocity and temperature variations can be neglected, we derive the most general constitutive relation consistent with symmetry constraints for the electric field in the presence of a strong magnetic field. This constitutive relation not only reproduces the phenomena of Ohmic decay, ambipolar diffusion, and Hall drift derived in a phenomenological model by Goldreich and Reisenegger, but also reveals terms in the evolution of the magnetic field which cannot easily be seen from such microscopic models. This formulation gives predictions for diffusion behaviors of small perturbations around a constant background magnetic field, and for the two-point correlation functions among various components of the electric and magnetic fields.

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References (50)

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Outline

Information

Phys. Rev. Research 6, L042050– Published 26 November, 2024
  • Received 2 August 2022
  • Revised 29 August 2024
  • Accepted 20 October 2024
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