We update the constraints on the fraction of the Universe that may have gone into primordial
black holes (PBHs) over the mass range 10− 5 to 10 50 g. Those smaller than∼ 10 15 g …

Axions comprise a broad class of particles that can play a major role in explaining the
unknown aspects of cosmology. They are also well-motivated within high energy physics …

The present white paper is submitted as part of the “Snowmass” process to help inform the
long-term plans of the United States Department of Energy and the National Science …

It is commonly assumed that the energy density of the Universe was dominated by radiation
between reheating after inflation and the onset of matter domination 54,000 years later …

The Review summarizes much of particle physics and cosmology. Using data from previous
editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average …

In this review article, we discuss the current status of particle dark matter, including
experimental evidence and theoretical motivations. We discuss a wide array of candidates …

We study the effects of long-lived massive particles, which decayed during the big-bang
nucleosynthesis (BBN) epoch, on the primordial abundance of light elements. Compared to …

This biennial Review summarizes much of particle physics. Using data from previous
editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average …

This Voyage 2050 paper highlights the unique science opportunities using spectral
distortions of the cosmic microwave background (CMB). CMB spectral distortions probe …

We compute cosmic microwave background (CMB) anisotropy constraints on exotic forms of
energy injection in electromagnetic (em) channels over a large range of timescales. We …