<b>Ford Motor Company Distinguished Lecture in Physics</b><br><i>Inflationary Cosmology: Is Our Universe Part of a Multiverse?</i>

Speaker: Alan H. Guth (MIT)

Reception preceding at 3:30 p.m., first floor East Hall North Atrium
(located directly behind the lecture hall facing Church Street)

Abstract: The inflationary theory is a twist on the conventional big bang theory, proposing a modification to the history of the universe during its first quadrillionth of a quadrillionth of a second. I will begin by explaining how inflation works, and then I will discuss some of the key properties of our universe that suggest that it actually arose from inflation. For example, the universe is found to be amazingly smooth when averaged over large regions, far smoother than would be expected from a normal explosion. Yet on smaller scales, the universe exhibits a complicated structure of stars, galaxies, and clusters of galaxies. Inflation can explain both the smoothness and the structure. After explaining these features of inflation, I will explain how almost all detailed versions of inflation give rise not merely to one universe, but to a multiverse: an infinite set of "pocket universes," each of which would be much larger than the region that we currently observe.