5 papers
Cosmological constraints and standard sirens forecasts for non-dynamical dark energy in Horndeski gravity
Marcello Miranda, Ruchika, Ivan De Martino +2
We investigate an analytically tractable sector of the Extended Cuscuton model, a non-dynamical dark-energy realization within the framework of viable Horndeski gravity. We focus o…
Present Day Cosmic Acceleration from SDSS and DESI BAO: A Call for Finer Tomography of the DESI Bright Galaxy Survey
Anna Chiara Ferri, Ruchika, Alessandro Melchiorri
The DESI collaboration's Data Release~2 (DR2) provides baryon acoustic oscillation (BAO) measurements from over 14 million galaxies and quasars, and a joint analysis of DESI BAO, C…
Optical depth to reionization in a Universe with multiple inhomogeneous domains
Shashank Shekhar Pandey, Ruchika, Subhadeep Mukherjee +1
We study the optical depth to reionization in a cosmological setting that includes backreaction from matter inhomogeneities, using the Buchert averaging formalism. We construct a s…
Hubble Tension and the G-step Model: Re-examination of Recent Constraints on Modified Local Physics
Leandros Perivolaropoulos, Ruchika
We critically examine recent claims challenging the viability of the G-step model (GSM) as a solution to the Hubble tension. The GSM proposes a 4 % increase in the effective…
Resilience and implications of adiabatic CMB cooling
Ruchika, William Giarè, Elsa M. Teixeira +1
We investigate potential deviations from the standard adiabatic evolution of the cosmic microwave background (CMB) temperature, , using the latest Sunyaev-Zeldovich…