63rd Alpheus Smith Lecture featuring Professor Wendy Freedman

In 1929, Carnegie astronomer Edwin Hubble discovered that the universe is expanding, and revolutionized our perspective on the universe. Decades of discovery followed. The launch of the Hubble Space Telescope in 1990 enabled astronomers to make measurements of the universe of unprecedented accuracy. Professor Freedman will describe how astronomers measure how fast the universe is expanding, a quantity known as the Hubble constant, which gives a measure of the size and the age of the universe.   Over the last decade, there has been mounting evidence for what has become known as the  ‘Hubble tension’.  Local measurements of the Hubble constant are at odds with those inferred from measurements of the background radiation left over from the Big Bang. This tension is potentially calling into question the standard model of cosmology, and raising the question of whether there is more exotic physics yet to be uncovered. Professor Freedman will present some new data from the recently launched James Webb Space Telescope that promises to resolve many of the issues currently confronting cosmology.