Quantum electrodynamical corrections to a magnetic dipole in general relativity

J. Pétri

doi:10.1093/mnras/stv2967

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arXiv · 1512.05805

Quantum electrodynamical corrections to a magnetic dipole in general relativity

J. Pétri

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Abstract

Magnetized neutron stars are privileged places where strong electromagnetic fields as high as $\BQ=4.4\times10^9$~T exist, giving rise to non-linear corrections to Maxwell equations described by quantum electrodynamics (QED). These corrections need to be included to the general relativistic (GR) description of a magnetic dipole supposed to be anchored in the neutron star. In this paper, these QED and GR perturbations to the standard flat space-time dipole are calculated to the lowest order in the fine structure constant~$α_{\rm sf}$ and to any order in the ratio $\Rs/R$ where $R$ is the neutron star radius and $\Rs$ its Schwarzschild radius. Following our new 3+1~formalism developed in a previous work, we compute the multipolar non-linear corrections to this dipole and demonstrate the presence of a small dipolar~$\ell=1$ and hexapolar~$\ell=3$ component.

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J. Pétri. 2015-12-17. Quantum electrodynamical corrections to a magnetic dipole in general relativity. https://doi.org/10.1093/mnras%2Fstv2967

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