Searching for Merging Supermassive Black Holes

At the center of most galaxies lie supermassive black holes. When galaxies merge, these giants eventually find one another and merge, emitting gravitational waves that ripple through space-time. Detecting these waves is key to understanding the universe’s largest black holes, which recent James Webb Space Telescope observations suggest are far more massive than previously thought.

In this Presidential Lecture, Chiara Mingarelli will discuss the hunt for merging supermassive black holes using a galaxy-sized detector that leverages pulsar stars — nature’s most precise cosmic clocks. She will explore how recent evidence of surprisingly massive black holes in the distant universe implies that giant binary black holes should exist in our cosmic neighborhood. She will also explain how she and her colleagues search for the distinct signatures of these systems, distinguishing them from the background “hum” of the universe, and what our current search limits reveal about the history of galaxy growth.