Description

Professor Chris Impey, Associate Dean for Science at the University of Arizona, will take you through how black holes emerge from the mathematics of general relativity, what we’ve learned about the formation and evolution of these mysterious objects, and how they can grow become the massive behemoths that sit at the centre of every galaxy.

Abstract

Black holes occupy a singular place in modern science and in the public mind. The idea of a star with gravity so strong that light can’t escape begins with the general theory of relativity. Yet even Einstein couldn’t accept the monstrous implications of his theory. It wasn’t until the late 1960’s that evidence for “dark stars” became compelling. Several dozen black holes in binary star systems have been identified. Over the next few decades astronomers realized that every galaxy hosts a massive black hole. These black holes are mostly quiescent, but when active, they become the brightest objects in the cosmos. Black holes are deceptively simple, described only by mass and spin, but Stephen Hawking showed they have temperature and must slowly evaporate. Currently, theorists struggle to understand the nature of the singularity, and what happens to information that falls into a black hole. For massive black holes, the challenge is to explain how they can grow to billions of times the Sun’s mass within a few hundred million years of the big bang. Study of black holes entered an exciting era with the detection of gravitational waves from merging black holes. Astronomers plan to use black holes, large and small, to test general relativity in new ways. Black holes have still not given up all their secrets.

Biography

Professor Chris Impey obtained his undergraduate degree in physics from the University of London and his PhD in astronomy from the University of Edinburgh in Scotland in 1981. He was a postdoctoral researcher at the University of Edinburgh, a Science Research Council / NATO Fellow at The University of Hawaii, and was a recipient of the Weingart Prize Fellowship at California Institute of Technology, before being appointed at the University of Arizona, where he has been since 1986, and is now the Associate Dean for Science. He has won numerous awards for both his research and teaching work. His work focusses on observational cosmology — using telescopes and other instruments to study the large-scale structure and evolution of the universe.

General inquiries: Should you have any accesibility needs, or any other concerns/questions, please email j.greenslade14@ic.ac.uk.

Image credit: NASA/JPL-Caltech