Axions as Dark Matter, Dark Energy, and Dark Radiation
Abstract
Axions and axion-like particles are ubiquitous in extensions of the Standard Model and offer a unifying framework for addressing open problems in cosmology. Depending on their mass and interactions, axions can act as dark matter, drive cosmic acceleration as dark energy, or contribute to the relativistic background as dark radiation. Motivated by the plenary talk at TAUP 2025, this proceeding reviews the phenomenology of light bosons in the early and late Universe, with a focus on the theoretical foundations, observational signatures, and experimental prospects. This contribution is intended as a compact mini-review, emphasizing representative mechanisms and observational targets rather than an exhaustive survey.
Cite
@article{arxiv.2509.17059,
title = {Axions as Dark Matter, Dark Energy, and Dark Radiation},
author = {Luca Visinelli},
journal= {arXiv preprint arXiv:2509.17059},
year = {2026}
}
Comments
14 pages + references. Invited contribution for the XIX International Conference on Topics in Astroparticle and Underground Physics (TAUP 2025), 24-30 Aug 2025, Xichang (China)