Description
We pursue a comprehensive approach towards the estimation of the Hubble constant by addressing two separate but interlinked sources of uncertainty: peculiar velocities and the calibration of the distance ladder. Peculiar velocities introduce noise in the Hubble diagram and can potentially bias the Hubble constant estimates derived from direct distance tracers. Traditionally, their impact is mitigated by applying velocity field corrections inferred from separate analyses. Simultaneously, it is typically assumed that direct distance tracers are already calibrated. We propose a unified framework that jointly calibrates the distance ladder—starting from geometric anchors, through Cepheid and Tip of the Red Giant Branch measurements, to Tully–Fisher galaxies—while simultaneously calibrating the peculiar velocity field (which probes the growth rate of structure) and the Hubble constant. This integrated approach allows for a robust, self-consistent accounting of the effect of distance ladder calibration, peculiar velocities, and for a joint inference of both the growth rate of matter and the Hubble constant. In this talk, I will present a preliminary set of results.
