August 23 Craig Hogan Public Lecture

Experiments with Space and Time




Paepcke Auditorium
6:00 pm

Speaker Ė Craig Hogan, Fermilab

Craig Hogan is Director of the Fermilab Center for Particle Astrophysics, and a Professor of Astronomy and Astrophysics at the University of Chicago. He earned his Ph.D. in 1980 at the University of Cambridge under Martin Rees, and after postdoctoral study at Chicago and Caltech, held faculty positions at the University of Arizona and the University of Washington, where he also served as Vice Provost for Research. Hoganís research has spanned a wide range of cosmology, including theoretical studies of the early universe and gravitational waves, as well as cosmological experiments. He was a member of one of the teams recognized by the 2011 Nobel Prize in Physics for discovering the acceleration of the universe. He is currently co-leading an effort at Fermilab to attempt the first measurement of a quantum behavior of space-time.

Topic

Space--- the familiar space we live in, right here and now--- is the first concept of physics we all learn as little kids, yet it is entangled with some of the deepest mysteries confronting physics. Space is based on the idea of locality, but experiments show that in reality, nothing happens at definite time or place, which suggests that space is not as real as it seems. It has been suggested that all the space of the universe began, and may end, dominated by the energy of the vacuum, expanding and devoid of particles; that when examined over very short time intervals, space as we know it does not even exist, but dissolves into a cloud of quantum indeterminacy, and constantly seethes in microscopic ambiguity; that space has either more than three dimensions or fewer, depending on how you look at it; that reality carries only a finite amount of information, and unfolds at the Planck frequency, about 10^44 bits per second. It may even be that all of these exotic possibilities actually apply in the real world.

At Fermilab, we are working on experiments including the Dark Energy Survey, the Fermilab Holometer, and the CMS experiment at CERN's Large Hadron Collider, that probe these ideas in very different ways. The talk will survey what we hope to learn from them.