Simulations and observational tests of primordial magnetic fields from Cosmic Microwave Background constraints

TL;DR

This paper uses cosmological simulations to explore how primordial magnetic fields, constrained by CMB observations, influence large-scale structures and observable signals, providing potential tests for these early universe fields.

Contribution

First to simulate primordial magnetic fields constrained by CMB data, analyzing their observable effects on cosmic structures and signals.

Findings

Differences in galaxy cluster signals are too small for current detection.

Filament signals could be tested with future SKA observations.

Full-sky statistical analyses can already constrain primordial magnetic field models.

Abstract

We present the first cosmological simulations of primordial magnetic fields derived from the constraints by the Cosmic Microwave Background observations, based on the fields' gravitational effect on cosmological perturbations. We evolved different primordial magnetic field models with the {\enzo} code and compared their observable signatures (and relative differences) in galaxy clusters, filaments and voids. The differences in synchrotron radio powers and Faraday Rotation measure from galaxy clusters are generally too small to be detected, whereas differences present in filaments will be testable with the higher sensitivity of the Square Kilometre Array. However, several statistical full-sky analyses, such as the cross-correlation between galaxies and diffuse synchrotron power, the Faraday Rotation structure functions from background radio galaxies, or the analysis of arrival direction of Ultra-High-Energy Cosmic Rays, can already be used to constrain these primordial field models.