5 papers
Directional Tests of the Cosmic Distance Duality Relation using Pantheon+ and BAO
Pushty Shrimankar, Gopal Kashyap
We present a model-independent test of anisotropy in the cosmic distance duality relation (CDDR), , using the Pantheon+ type Ia supernova sample and baryon acousti…
Unimodular Diffusion and Interacting Vacuum Cosmology
Gopal Kashyap, Naveen K. Singh
We investigate the correspondence between unimodular diffusion cosmology and interacting dark sector models at the background and linear perturbation levels. In the diffusion frame…
Constraints on Axion-Photon Mixing from Fast Radio Burst Dispersion Measures
Gunalan Muthusami, Gopal Kashyap
Fast radio bursts (FRBs) offer a powerful probe of the ionized Universe through their dispersion measures (DM). While a significant fraction of the DM arises from the intergalactic…
Matter Dipole and Hubble Tension due to Large Wavelength Perturbations
Gopal Kashyap, Naveen K. Singh, Pankaj Jain
We theoretically analyze the dipole anisotropy observed in the quasar distribution from the CatWISE2020 catalog. The catalog data shows a peak around , suggesting the p…
Stability of Neutron Star and Cosmological Constant
Naveen K. Singh, Gopal Kashyap
We derive the equation for pressure within a neutron star, taking into account a non-zero cosmological constant (). We then examine the stability of the neutron star's equilibr…