Swampland bounds on dark sectors

• Published in: The journal of high energy physics 2022-11, Vol.2022 (11), p.121-31, Article 121
• Main Authors: Montero, Miguel, Muñoz, Julian B., Obied, Georges
• Format: Article
• Language: English
• Subjects: Charged particles; Classical and Quantum Gravitation; Dark matter; Effective Field Theories; Elementary Particles; High energy physics; Mathematical models; Models for Dark Matter; Parameters; Photons; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum gravity; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; String Models; String Theory
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP11(2022)121

A bstract We use Swampland principles to theoretically disfavor regions of the parameter space of dark matter and other darkly charged particles that may exist. The Festina Lente bound, the analogue of the Weak-Gravity conjecture in de Sitter, places constraints on the mass and charge of dark particles, which here we show cover regions in parameter space that are currently allowed by observations. As a consequence, a broad set of new ultra-light particles are in the Swampland, independently of their cosmic abundance, showing the complementarity of Quantum Gravity limits with laboratory and astrophysical studies. In parallel, a Swampland bound on the UV cutoff associated to the axion giving a Stückelberg photon its longitudinal mode translates to a new constraint on the kinetic mixings and masses of dark photons. This covers part of the parameter space targeted by upcoming dark-photon direct-detection experiments. Moreover, it puts astrophysically interesting models in the Swampland, including freeze-in dark matter through an ultra-light dark photon, as well as radio models invoked to explain the 21-cm EDGES anomaly.