collaborators

5 papers

astro-ph.CO2025

Multi-tracing the primordial Universe with future surveys

Mponeng Kopana, Sheean Jolicoeur, Roy Maartens

The fluctuations generated by Inflation are nearly Gaussian in the simplest models, but may be non-Gaussian in more complex models, potentially leading to signatures in the late Un…

astro-ph.CO2024

Apparent parity violation in the observed galaxy trispectrum

Pritha Paul, Chris Clarkson, Roy Maartens

Recent measurements of the 4-point correlation function in large-scale galaxy surveys have found apparent evidence of parity violation in the distribution of galaxies. This cannot…

astro-ph.CO2024

Covariant cosmography: the observer-dependence of the Hubble parameter

Roy Maartens, Jessica Santiago, Chris Clarkson +2

The disagreement between low- and high-redshift measurements of the Hubble parameter is emerging as a serious challenge to the standard model of cosmology. We develop a covariant c…

astro-ph.CO2024

The HI intensity mapping power spectrum: insights from recent measurements

Hamsa Padmanabhan, Roy Maartens, Obinna Umeh +1

The first direct measurements of the HI intensity mapping power spectrum were recently made using the MeerKAT telescope. These measurements are on nonlinear scales, at redshifts 0.…

astro-ph.CO2024

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…