Webinaires de l'Action Dark Energy

The Hubble Tension

by Prof. George Efstathiou (Kavli Institute for Cosmology, Cambridge)

Europe/Paris
Zoom (Lien communiqué le jour-même sur la liste de l'action Dark Energy)

Zoom

Lien communiqué le jour-même sur la liste de l'action Dark Energy

Description

I will review the constraints on H_0 from the Planck CMB measurements and compare the best fit Planck model with recent results from ACTpol.
The CMB value of H_0 is secure, yet is in tension with Cepheid based measurements of H_0.  Although the CMB  value is based on theLambda CDM cosmology, there has been no compelling theoretical modification of the model that can explain the tension. I will therefore explore whether systematic errors may be affecting the Cepheid distance scale and if so, what must these errors look like.