External Fields as a Probe for Fundamental Physics

TL;DR

Quantum vacuum experiments using strong electromagnetic fields are emerging as a versatile approach to explore fundamental physics, capable of detecting new particles and distinguishing between different theoretical models.

Contribution

This review highlights recent advances in optical experiments with strong electromagnetic fields as probes for new physics beyond the Standard Model.

Findings

Optical signatures can indicate the presence of new light particles.

Experiments can differentiate between various particle-physics scenarios.

Specialized setups can reveal microscopic properties of fundamental particles.

Abstract

Quantum vacuum experiments are becoming a flexible tool for investigating fundamental physics. They are particularly powerful for searching for new light but weakly interacting degrees of freedom and are thus complementary to accelerator-driven experiments. I review recent developments in this field, focusing on optical experiments in strong electromagnetic fields. In order to characterize potential optical signatures, I discuss various low-energy effective actions which parameterize the interaction of particle-physics candidates with optical photons and external electromagnetic fields. Experiments with an electromagnetized quantum vacuum and optical probes do not only have the potential to collect evidence for new physics, but special-purpose setups can also distinguish between different particle-physics scenarios and extract information about underlying microscopic properties.