Abstract This Primer examines Skilling's nested sampling algorithm for Bayesian inference
and, more broadly, multidimensional integration. The principles of nested sampling are …

Since the discovery of neutrino oscillations, we know that neutrinos have non-zero mass.
However, the absolute neutrino-mass scale remains unknown. Here we report the upper …

Cosmic inflation provides a window to the highest energy densities accessible in nature, far
beyond those achievable in any realistic terrestrial experiment. Theoretical insights into the …

Cosmological neutrino mass bounds are becoming increasingly stringent. The latest limit
within Λ CDM from Planck 2018+ ACT lensing+ DESI is∑ m ν< 0.072 eV at 95% CL, very …

We report the results of the second measurement campaign of the Karlsruhe Tritium
Neutrino (KATRIN) experiment. KATRIN probes the effective electron anti-neutrino mass …

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 …

The cosmic neutrino background (CNB) is a definite prediction of the standard cosmological
model and its direct discovery would represent a milestone in cosmology and neutrino …

Stochastic gravitational wave (GW) backgrounds from first-order phase transitions are an
exciting target for future GW observatories and may enable us to study dark sectors with very …

Astroparticle physics is undergoing a profound transformation, due to a series of
extraordinary new results, such as the discovery of high-energy cosmic neutrinos with …

Sub-GeV dark matter (DM) particles produced via thermal freeze-out evade many of the
strong constraints on heavier DM candidates but at the same time face a multitude of new …