We review applications of string theory to cosmology, from primordial times to the present-
day accelerated expansion. Starting with a brief overview of cosmology and string …

When the universe is treated as a quantum system, it is described by a wave function. This
wave function is a function not only of the matter fields, but also of spacetime. The no …

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

A bstract In this paper, we propose a new Swampland condition, the Trans-Planckian
Censorship Conjecture (TCC), based on the idea that in a consistent quantum theory of …

We systematically review some standard issues and also the latest developments of
modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time …

We revisit the possibility that the stochastic common-spectrum process recently detected by
the NANOGrav pulsar timing array experiment could be due to primordial gravitational …

Gravitational waves (GWs) have a great potential to probe cosmology. We review early
universe sources that can lead to cosmological backgrounds of GWs. We begin by …

Over recent decades, the role of torsion in gravity has been extensively investigated along
the main direction of bringing gravity closer to its gauge formulation and incorporating spin …

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark
discovery, potentially providing a significant clue to some of our most basic, big-picture …

Despite its continued observational successes, there is a persistent (and growing) interest in
extending cosmology beyond the standard model, Λ CDM. This is motivated by a range of …