activity
20242026
collaborators

8 papers

astro-ph.CO2026

A refined method for measuring cosmological distances using variability and proper motions in AGN with VLBI-detected counter-jets

Jeffrey A. Hodgson, Anthony Carr, David Parkinson +6

In a previous paper, we described a `standard speed-gun' (SSG) distance that uses the speed of light to standardize a ruler under the assumption that the radio variability seen in…

astro-ph.CO2026

Model independent test of the FLRW metric and the curvature in light of DESI DR2

Cléa Millard, Benjamin L'Huillier, Marian Douspis

We perform a data-driven test of the FLRW metric and the flatness of the Universe, independently of any Dark Energy model, and in light of the latest DESI DR2 results. We use Panth…

astro-ph.CO2026

Non-parametric estimation of the baryon gas fraction and the cosmological bias with clusters

Hyeon Kim, Raphaël Wicker, Benjamin L'Huillier +3

X-ray observations of galaxy clusters allow us to estimate the gas fraction, and thus the baryon fraction, and its evolution over time. This offers an additional cosmological probe…

astro-ph.CO2025

The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics

Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533

The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…

astro-ph.CO2025

An Analysis of Variance of the Pantheon+ Dataset: Systematics in the Covariance Matrix?

Ryan Keeley, Arman Shafieloo, Benjamin L'Huillier

We investigate the statistics of the available Pantheon+ dataset. Noticing that the value for the best-fit CDM model to the real data is small, we quantify how significa…

astro-ph.CO2025

Litmus tests of the flat CDM model and model-independent measurement of with LSST and DESI

Benjamin L'Huillier, Ayan Mitra, Arman Shafieloo +2

In this analysis we apply a model-independent framework to test the flat CDM cosmology using simulated SNIa data from the upcoming Legacy Survey of Space and Time (LSST) and co…