TITLE: Of Metronomes and Pendulum Clocks and Fiber Lasers

SPEAKER: Prof. Kurt Wiesenfeld

TIME: Thursday April 8 at 3 PM

PLACE: George P. Williams, Jr. Lecture Hall, (Olin 101)

Some 344 years ago (give or take) Chritiaan Huygens observed two pendulum clocks spontaneously synchronize; the pendulums always locked in anti-phase. He traced the interaction to the minute motion of the wooden beam which supported the two clocks. In contrast, a simple classroom demonstration using metronomes in place of pendulum clocks -- with the same support-coupling mechanism -- yields stable in-phase synchronization. I'll explore (and explain) the reasons behind this difference. I'll also describe a surprising connection with the problem of generating coherent radiation from a laser array, a longstanding (and recently achieved) goal of laser physicists.