Although the dark matter is usually assumed to be made up of some form of elementary
particle, primordial black holes (PBHs) could also provide some of it. However, various …

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 …

The possibility that the dark matter comprises primordial black holes (PBHs) is considered,
with particular emphasis on the currently allowed mass windows at 1 0 16–1 0 17 g, 1 0 20 …

Abstract Primordial Black Holes (PBH) could be the cold dark matter of the universe. They
could have arisen from large (order one) curvature fluctuations produced during inflation that …

Primordial black holes (PBHs) could provide the dark matter in various mass windows below
102 M⊙ and those of 30 M⊙ might explain the LIGO events. PBHs much larger than this …

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

Deviations from the blackbody spectral energy distribution of the cosmic microwave
background (CMB) are a precise probe of physical processes active both in the early …

The recent detection of a stochastic gravitational wave background (SGWB) at nanohertz
frequencies by pulsar timing arrays (PTAs) has sparked a flurry of interest. Beyond the …

Spectral distortions (SDs) of the cosmic microwave background (CMB) provide a powerful
tool for studying particle physics. Here we compute the distortion signals from decaying …

Axion-like particles (ALPs) decaying into photons are known to affect a wide range of
astrophysical and cosmological observables. In this study we focus on ALPs with masses in …