Polarization-dependent heating of the cosmic microwave background radiation by a magnetic field

TL;DR

This paper investigates how strong magnetic fields in the vicinity of magnetars can cause polarization-dependent heating of the cosmic microwave background, due to quantum electrodynamics effects, but detection remains challenging.

Contribution

It presents a theoretical analysis of CMB spectrum distortion and polarization effects caused by magnetic fields through QED vacuum interactions, highlighting the magnitude and detection difficulties.

Findings

Magnetic fields near magnetars can significantly distort the CMB spectrum.

The polarization of CMB radiation is affected by magnetic field coupling.

Current angular resolution limits hinder detection of these effects.

Abstract

The changes in the cosmic microwave background (CMB) spectrum seen as an increase of temperature due to a strong magnetic field are determined and their influence on the polarization of the radiation is exhibited. The effect is due to the coupling of the CMB photons to the magnetic field in the QED vacuum via the interaction with virtual pairs. In spite of the fact that the distortion of the CMB spectrum for magnetic fields that exist in the vicinity of magnetars is quite large, this effect is very difficult to detect at present because the required angular resolutions is not yet available.