96 citations · 454 across the 15 of their papers we have counts for
16 papers
Testing Schouten--Codazzi Gravity: Cosmological Constraints and Deviations from CDM
Andoni Fontanet, Andrea Valencia, Shahnawaz A. Adil +4
Schouten--Codazzi gravity (SCG) admits a cosmological background that extends flat CDM by one integration constant, . Its contribution to the Friedmann equation scales as $…
Reconstructing sign-switching dark energy histories: Scalar-field regularity, conditional potential comparison, and representative dynamics
Shahnawaz A. Adil, Özgür Akarsu, Mariam Bouhmadi-López +3
Phenomenologically similar sign-switching dark-energy histories need not have comparable scalar-field realizations. We reconstruct minimally coupled scalars with fixed kinetic sign…
Dissipative Cosmology and the Nature of Dark Energy: Insights from Bulk Viscosity with DESI DR2 observations
Shahnawaz A. Adil, Sonej Alam, Somasri Sen +1
We explore a cosmological model in which dark energy is described by a bulk viscous fluid, providing a dissipative mechanism for late-time cosmic acceleration. Considering both min…
Background-level reconstruction of scalar-field potentials from dark-energy histories and comparison with analytic potential families
Shahnawaz A. Adil, Miguel A. Zapata, Özgür Akarsu +1
We present a unified \emph{background-level} framework that maps a prescribed late-time dark-energy density history onto an effective scalar-field description in a…
How Holographic is the Dark Energy? A Spline Nodal reconstruction approach
Miguel A. Zapata, Gabriela Garcia-Arroyo, Shahnawaz A. Adil +1
In this work, we explore the generalized holographic dark energy (HDE) scenario. We relate the HDE density to the future-horizon scale via a non-parametric function, which is recon…
Updated Constraints on Omnipotent Dark Energy: A Comprehensive Analysis with CMB and BAO Data
Enrico Specogna, Shahnawaz A. Adil, Emre Ozulker +4
In this work, we present updated observational constraints on the parameter space of the DMS20 dark energy model, a member of the omnipotent dark energy (ODE) class. Our analysis c…
Exploring Alternative Cosmologies with the LSST: Simulated Forecasts and Current Observational Constraints
Dharmendra Kumar, Ayan Mitra, Shahnawaz A. Adil +1
In recent years, the Lambda Cold Dark Matter (LCDM) model, which has been pivotal in cosmological studies, has faced significant challenges due to emerging observational and theore…
Revisiting the Concordance CDM model using Gamma-Ray Bursts together with Supernovae Ia and Planck data
Shahnawaz A. Adil, Maria G. Dainotti, Anjan A. Sen
The Hubble constant, , tension is the tension among the local probes, Supernovae Ia, and the Cosmic Microwave Background Radiation. It has been almost a decade, and this tensi…
Negative cosmological constant in the dark energy sector: tests from JWST photometric and spectroscopic observations of high-redshift galaxies
Nicola Menci, Shahnawaz A. Adil, Upala Mukhopadhyay +2
Early observations with the James Webb Space Telescope (JWST) have revealed the existence of an unexpectedly large abundance of extremely massive galaxies at redshifts $z \gtrsim 5…
Dark energy in light of the early JWST observations: case for a negative cosmological constant?
Shahnawaz A. Adil, Upala Mukhopadhyay, Anjan A. Sen +1
Early data from the James Webb Space Telescope (JWST) has uncovered the existence of a surprisingly abundant population of very massive galaxies at extremely high redshift, which a…
Omnipotent dark energy: A phenomenological answer to the Hubble tension
Shahnawaz A. Adil, Ozgur Akarsu, Eleonora Di Valentino +4
This paper introduces the class of omnipotent dark energy (DE) models characterized by nonmonotonic energy densities that are capable of attaining negative values with correspondin…
increases with effective redshift in CDM cosmology
Shahnawaz A. Adil, Özgür Akarsu, Mohammad Malekjani +4
Hubble constant and weighted amplitude of matter fluctuations determinations are biased to higher and lower values, respectively, in the late Universe with respect to e…
Cosmological Evolution in Bimetric Gravity: Observational Constraints and LSS Signatures
Ajay Bassi, Shahnawaz A. Adil, Manvendra Pratap Rajvanshi +1
Bimetric gravity is an interesting alternative to standard GR given its potential to provide a concrete theoretical framework for a ghost-free massive gravity theory. Here we inves…
Do cosmological observations allow a negative ?
Anjan A. Sen, Shahnawaz A. Adil, Somasri Sen
In view of the recent measurement of from HST and SH0ES team, we explore the possibility of existence of a negative cosmological constant (AdS vacua in the dark energy sect…
Late time acceleration due to generic modification of gravity and Hubble tension
Shahnawaz A. Adil, Mayukh R. Gangopadhyay, M. Sami +1
We consider a scenario of modified gravity, which is generic to late-time acceleration, namely, acceleration in the Jordan frame and no acceleration in the Einstein frame. The poss…
Observational Constraints on Axion(s) Dark Energy with a Cosmological Constant
Ruchika, Shahnawaz A. Adil, Koushik Dutta +2
The present work deals with a dark energy model that has an oscillating scalar field potential along with a cosmological constant (CC). The oscillating part of the potential repres…