The Physics Centennial Speaker Series concludes May 5 with “Mysteries of the Dark Universe,” a talk by Edward W. “Rocky” Kolb, chair of the Department of Astronomy and Astro-physics, University of Chicago.

Those mysteries stem from observations suggesting that most of the mass of the universe is in a mysterious form called dark matter and most of the energy in the universe is in an even more mysterious form called dark energy.

Kolb’s talk, free and open to the public, is scheduled for 7 p.m. in 123 Sciences Lecture Hall.

The physicist is renowned for his theoretical research at the interface of particle physics and cosmology — and, lucky for lay audiences, he is described as “a celebrated communicator of science.”

He has appeared in several television productions, including most recently, a Discovery Channel program in which he interviewed Stephen Hawking.

Kolb is a fellow of the American Academy of Arts and Sciences and a fellow of the American Physical Society. He was the recipient of the 2003 Oersted Medal of the American Association of Physics Teachers and the 1993 Quantrel Prize for teaching excellence at the University of Chicago.

All Seminars and Colloquia: calendar.ucdavis.edu