Cosmological parameters from galaxy clustering and weak lensing on ~Megaparsec scales

Wednesday 30 Mar 2022 @ 12:00 p.m., David Caro building, Level 7 Conference Room (+Zoom) Dr Ben Wibking, ANU; Email: ben.wibking[at]


Since the discovery of the accelerating expansion of the Universe, a fundamental question for physics has been the nature of this acceleration – is it consistent with a cosmological constant, cold dark matter Universe governed by General Relativity? One of the most precise probes of this is weak gravitational lensing. This can be combined with galaxy clustering and examined on nonlinear scales to obtain very precise measurements of cosmological parameters. I present constraints from galaxy clustering and weak lensing on ~Megaparsec scales using the galaxy catalogue from the Baryon Oscillation Spectroscopic Survey. I show that these data lead to a statistically significant tension in the amplitude of matter fluctuations at low redshift compared to that measured by the Planck cosmic microwave background satellite.