94 citations · 241 across the 18 of their papers we have counts for
18 papers
Constraining inflationary models via de-Sitterization of Bianchi Cosmologies
Apurba Samanta, Rahul Kothari
Our Universe is isotropic and homogeneous when we observe it on Mpc length scales. It is desirable that present state of the Universe has no dependence on its initial geo…
Constraining Lorentz Violation using 21cm and CMB Cross Correlations
Bhuwan Joshi, Rahul Kothari, Shyam Chaudhary
Lorentz symmetry is a fundamental pillar of modern Physics, yet high-energy theories often predict its violation. One potential signature of such a violation is cosmic birefringenc…
Constraining Statistical Isotropy using 21cm Power Spectrum and Bispectrum
Bhuwan Joshi, Rahul Kothari
The Cosmological Principle states that the universe is statistically isotropic and homogeneous on large length scales, typically Mpc. A detection of significant deviati…
A wide-angle formulation of foreground filters for HI intensity mapping
Rahul Kothari, Roy Maartens
Neutral hydrogen intensity mapping can in principle deliver rapid and large-volume cosmological surveys with exquisitely accurate redshifts that are determined directly from imagin…
Probing Cosmology beyond CDM using the SKA
Shamik Ghosh, Pankaj Jain, Rahul Kothari +3
The cosmological principle states that the Universe is statistically homogeneous and isotropic at large distance scales. There currently exist many observations which indicate a de…
A study of Dipolar Signal in distant Quasars with various observables
Rahul Kothari, Mohit Panwar, Gurmeet Singh +2
We study the signal of anisotropy in AGNs/quasars of CatWISE2020 catalogue using different observables. It has been reported earlier that this data shows a strong signal of dipole…
Superhorizon perturbations: A possible explanation of the Hubble--Lemaître Tension and the Large Scale Anisotropy of the Universe
Prabhakar Tiwari, Rahul Kothari, Pankaj Jain
Current cosmological observations point to a serious discrepancy between the observed Hubble parameter obtained using direct and cosmic microwave background radiation (CMBR) measur…
Lensing contribution to the 21cm intensity bispectrum
Rahul Kothari, Roy Maartens
Intensity maps of the 21cm emission line of neutral hydrogen are lensed by intervening large-scale structure, similar to the lensing of the cosmic microwave background temperature…
Full-sky bispectrum in redshift space for 21cm intensity maps
Ruth Durrer, Mona Jalilvand, Rahul Kothari +2
We compute the tree-level bispectrum of 21cm intensity mapping after reionisation. We work in the directly observable angular and redshift space, focusing on equal-redshift correla…
B-Mode auto-bispectrum due to matter bounce
Rahul Kothari, Debottam Nandi
Primordial Gravitational waves leave polarization imprints on the Cosmic Microwave Background (CMB). In this article, we investigate polarization bispectrum, which is also referred…
A comprehensive study of Modulation effects on CMB Polarization
Rahul Kothari
The Cosmic Microwave Background is characterized by temperature and linear polarization fields. Dipole modulation in the temperature field has been extensively studied in the conte…
Torsion driven Inflationary Magnetogenesis
M. V. S. Saketh, R. Kothari, P. Jain
We show that breaking of the conformal invariance of electromagnetic Lagrangian which is required for inflationary magnetogenesis arises naturally in the Poincar{é} Gauge Theory. W…
Probing statistical isotropy of cosmological radio sources using SKA
Shamik Ghosh, Pankaj Jain, Gopal Kashyap +3
There currently exist many observations which are not consistent with the cosmological principle. We review these observations with a particular emphasis on those relevant for Squa…
A Model for Dipole Modulation of CMBR Polarization
Rahul Kothari
I propose a model of dipole modulation in Cosmic Background Microwave Radiation (CMBR) polarization fields Q and U. It is shown that the modulation leads to correlations between l…
Dipole Modulation of Cosmic Microwave Background Temperature and Polarization
Shamik Ghosh, Rahul Kothari, Pankaj Jain +1
We propose a dipole modulation model for the Cosmic Microwave Background Radiation (CMBR) polarization field. We show that the model leads to correlations between l and l+1 multipo…
Imprint of Inhomogeneous and Anisotropic Primordial Power Spectrum on CMB Polarization
Rahul Kothari, Shamik Ghosh, Pranati K. Rath +2
We consider an inhomogeneous model and independently an anisotropic model of primordial power spectrum in order to describe the observed hemispherical anisotropy in Cosmic Microwav…
Cosmological Power Spectrum in Non-commutative Space-time
Rahul Kothari, Pranati K. Rath, Pankaj Jain
We propose a generalized star product which deviates from the standard product when the fields at evaluated at different space-time points. This produces no changes in the standard…
Dipole anisotropy in sky brightness and source count distribution in radio NVSS data
Prabhakar Tiwari, Rahul Kothari, Abhishek Naskar +2
We study the dipole anisotropy in number counts and flux density weighted number counts {or sky brightness} in the NRAO VLA Sky Survey (NVSS) data. The dipole anisotropy is expecte…