12:00–1:00 pm Zoom
Jose Luis Bernal (Johns Hopkins University) "The trouble with H0 (and beyond)"
The distance ladder using supernovae yields higher values of the Hubble constant H0 than those inferred from the cosmic microwave background (CMB) and galaxy surveys when the standard cosmological model, LCDM, is assumed. This discrepancy, known as the “Hubble tension”, has motivated the exploration of alternative cosmological models in which higher values of H0 can be obtained from CMB measurements and galaxy surveys. But these modifications also affect other quantities; in particular, the effects on the cosmic times are usually neglected. The value of H0 is related to the sound horizon at CMB decoupling (or at radiation drag), but also to the matter density and to the age of the Universe. I will discuss the current state of the Hubble tension and the features that alternative models must include to reconcile all measurements. I will also present the use of ternary plots as a powerful diagnostic tool of consistency.