Randomized trial tests cosmic isotropy in galaxy clusters, suggesting potential spatial variation in expansion rate.
Key Points
This study aims to investigate the isotropy of the local Universe using scaling relations of galaxy clusters. It explores whether deviations in cosmic expansion can be detected.
Analyzed up to 570 galaxy clusters with properties measured at X-ray, microwave, and infrared wavelengths.
Constructed ten different cluster scaling relations to assess isotropy and bulk flows.
Implemented Monte Carlo simulations to evaluate the statistical significance of observed anisotropies.
Detected a 9% spatial variation in H0 between specific sky coordinates, indicating anisotropy.
Observed anisotropy presents a nearly dipole form with a statistical significance greater than 5σ.
Proposed that a ~900 km/s bulk flow may extend to at least ~500 Mpc, contributing to the findings.