Title and Abstract for Jo's talk:
How fast is the universe growing?
Abstract: There is currently a tension between various measurements of the expansion rate of the universe. I will give a recap of this issue, and talk about how we use the Cosmic Microwave Background, our most distant observation, to infer the local expansion rate of space. I will explain what assumptions we make about the cosmological model in doing so, and how we might modify this model to bring different measurements of the expansion rate better in line. I will talk about new measurements we are making in Chile to improve estimates of the Hubble constant derived from the CMB, using the Atacama Cosmology Telescope, and the upcoming Simons Observatory.