Abstract The standard Λ Cold Dark Matter (ΛCDM) cosmological model provides a good
description of a wide range of astrophysical and cosmological data. However, there are a …

The simplest ΛCDM model provides a good fit to a large span of cosmological data but
harbors large areas of phenomenology and ignorance. With the improvement of the number …

A number of challenges to the standard Λ CDM model have been emerging during the past
few years as the accuracy of cosmological observations improves. In this review we discuss …

Despite the remarkable success of the Λ Cold Dark Matter (Λ CDM) cosmological model, a
growing discrepancy has emerged (currently measured at the level of∼ 4− 6 σ) between the …

The current cosmological probes have provided a fantastic confirmation of the standard Λ
Cold Dark Matter cosmological model, which has been constrained with unprecedented …

Particle physics today faces the challenge of explaining the mystery of dark matter, the origin
of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent …

The dawn of the twenty-first century came with very positive prospects for gravity, cosmology,
and astrophysics. Technological progress made it possible for cosmology to enter to its …

We explore the possibility that a confining first-order phase transition of a nearly-conformal
dark sector generates the reported NANOGrav signal of a stochastic gravitational wave …

New early dark energy (NEDE) is a component of vacuum energy at the electron volt scale,
which decays in a first-order phase transition shortly before recombination [F. Niedermann …

Recent pulsar timing data reported by the NANOGrav collaboration may indicate the
existence of a stochastic gravitational wave background around f∼ 10− 8 Hz. We explore a …