How do you know if you ran through a wall?

TL;DR

This paper proposes that a network of atomic magnetometers could detect domain walls from axion-like fields, offering a new terrestrial method to explore dark energy and dark matter models unconstrained by astrophysics.

Contribution

It introduces a novel terrestrial detection approach for topological defects from axion-like fields using synchronized atomic magnetometers.

Findings

A network of magnetometers can detect wall-crossing events.

Terrestrial experiments can probe previously unconstrained model parameters.

Detection sensitivity surpasses current astrophysical limits.

Abstract

Stable topological defects of light (pseudo)scalar fields can contribute to the Universe's dark energy and dark matter. Currently the combination of gravitational and cosmological constraints provides the best limits on such a possibility. We take an example of domain walls generated by an axion-like field with a coupling to the spins of standard-model particles, and show that if the galactic environment contains a network of such walls, terrestrial experiments aimed at detection of wall-crossing events are realistic. In particular, a geographically separated but time-synchronized network of sensitive atomic magnetometers can detect a wall crossing and probe a range of model parameters currently unconstrained by astrophysical observations and gravitational experiments.