학술논문

The Physics of Light Relics
Document Type
Working Paper
Source
Subject
High Energy Physics - Phenomenology
Astrophysics - Cosmology and Nongalactic Astrophysics
Language
Abstract
Many well-motivated extensions of the Standard Model predict the existence of new light species that may have been produced in the early universe. Prominent examples include axions, sterile neutrinos, gravitinos, dark photons, and more. The gravitational influence of light relics leaves imprints in the cosmic microwave background fluctuations, the large-scale structure of the universe and the primordial element abundances. In this paper, we detail the physics of cosmological light relics, and describe how measurements of their relic density and mass serve as probes of physics beyond the Standard Model. A measurement of the light relic density at the precision of upcoming cosmological surveys will point the way toward new physics or severely constrain the range of viable extensions to the Standard Model.
Comment: Contribution to Snowmass 2021. 59 pages, 12 figures