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 …

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 Hubble tension has now grown to a level of significance which can no longer be
ignored and calls for a solution which, despite a huge number of attempts, has so far eluded …

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

We review recent trends in inflationary dynamics in the context of viable modified gravity
theories. After providing a general overview of the inflationary paradigm emphasizing on …

We present results from an analysis of all data taken by the BICEP2, Keck Array, and
BICEP3 CMB polarization experiments up to and including the 2018 observing season. We …

We review the current status of Early Dark Energy (EDE) models proposed to resolve the
“Hubble tension”, the discrepancy between “direct” measurements of the current expansion …

We present a sample-variance-limited measurement of the temperature power spectrum
(TT) of the cosmic microwave background using observations of a∼ 1500 deg 2 field made …

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 …

A bstract In recent years, several pulsar timing array collaborations have reported first hints
for a stochastic gravitational wave background at nano-Hertz frequencies. Here we …