5 papers
Cosmological consequences of a dynamical dark matter in the light of DESI DR2 measurements
Abhijith Ajith, Utkarsh Kumar
Recent DESI results exhibit preference for a Null Energy Condition violating dynamical dark energy, with early phantom behaviour. We explore an alternative interpretation in which…
Primordial Gravitational Wave Background as a Probe of the Primordial Black Holes
Utkarsh Kumar
We study the formation of primordial black holes (PBHs) from the collapse of density perturbations induced by primordial gravitational waves (PGWs). The PGWs' interpretation of the…
Disentangling the Origins of the NANOGrav Signal: Early Universe Models and Bounds
Ido Ben-Dayan, Utkarsh Kumar, Amresh Verma
We investigate whether an Early-Universe stochastic gravitational-wave background (SGWB) can account for the common spectrum process reported by NANOGrav, while also being consiste…
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…
Evidence for non-cold dark matter from DESI DR2 measurements
Utkarsh Kumar, Abhijith Ajith, Amresh Verma
We investigate potential deviations from cold dark matter (CDM) using the latest Baryon Acoustic Oscillations (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI…