Dr. Heidi Wu

Assistant Professor

Boise State University

Host: Su

Title: Probing Cosmic Acceleration with Galaxy Clusters

Abstract: The accelerated expansion of the Universe is one of the biggest puzzles in physics: Why is gravity repulsive rather than attractive on distance scales larger than a few million lightyears? Cosmic acceleration slows down the growth of structure, and we can use galaxy clusters — the largest gravitationally bound objects in the Universe — to probe the nature of cosmic acceleration.  In this talk, I will first introduce our current understanding of the Universe.  I will then discuss how we use sky surveys of galaxy clusters to measure cosmic acceleration and how several ambitious ground- and space-based missions will revolutionize our understanding of the Universe.