16:00, November 29, Templeman Seminar Room 7
Abstract: If I fix one end of a belt to a chair and give it one 360-degree twist along the length of it, I can’t undo this twist without letting the other end out of my hands. But if I instead give it two full twists along the length, I can straighten it without letting go! (An interactive demonstration will be provided so the audience can confirm this for themselves.) I will give the mathematical explanation for this phenomenon by discussing the geometry of rotations in three dimensions, and the topology of the rotation group SO(3). I’ll discuss the relevance of these ideas to theoretical physics, particularly the physics of elementary particles, and, time permitting, hopefully use it to explain part of the structure of the Periodic Table of elements.