Physics Colloquium, October 1, 2002

Lattice QCD enters the Real World

Peter Lepage

Cornell University

Lattice QCD, the fundamental theory of subnuclear structure, is almost 30 years old. Until two years ago, however, attempts to analyze the theory numerically were stymied by our inability to simulate efficiently the effects of quark vacuum polarization. Consequently most results had uncontrolled systematic errors of order 15-20% or more. Algorithmic and theoretical developments in the late 1990s led to a breakthrough two years ago that makes high-precision, nonperturbative QCD calculations possible for the first time in history. This has important implications for heavy-quark and Standard Model physics, and potentially also for beyond the Standard Model. It also is a major development in the history of quantum field theory. This talk is a non-technical review of the conceptual ideas behind this revolutionary development in strong-interaction physics, together with a survey of the current impact on theoretical and experimental particle physics, and prospects for the future.

3.30 p.m., Smith Laboratory, Room 1005

Refreshments served in Smith 1094 at 3:00 p.m.