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 …

Primordial nucleosynthesis is one of the three historical evidences for the big bang model,
together with the expansion of the universe and the cosmic microwave background. There is …

Various pulsar timing array (PTA) experiments (NANOGrav, EPTA, PPTA, CPTA, including
data from InPTA) very recently reported evidence for excess red common-spectrum signals …

The European Space Agency's Planck satellite, which was dedicated to studying the early
Universe and its subsequent evolution, was launched on 14 May 2009. It scanned the …

The strong discrepancy between local and early-time (inverse distance ladder) estimates of
the Hubble constant H 0 could be pointing towards new physics beyond the concordance Λ …

We present cosmological parameter results from the final full-mission Planck measurements
of the cosmic microwave background (CMB) anisotropies, combining information from the …

We present in this work a new calculation of the standard-model benchmark value for the
effective number of neutrinos, $ N_ {\rm eff}^{\rm SM} $, that quantifies the cosmological …

We revisit the decoupling of neutrinos in the early universe with flavour oscillations. We
rederive the quantum kinetic equations which determine the neutrino evolution based on a …

The Simons Observatory (SO) is a new cosmic microwave background experiment being
built on Cerro Toco in Chile, due to begin observations in the early 2020s. We describe the …

This paper introduces C olossus, a public, open-source python package for calculations
related to cosmology, the large-scale structure (LSS) of matter in the universe, and the …