Sean will given the topology seminar this week, Thursday at 3:30 in 514.

Title: Bridge number of knots obtained by twisting

Abstract: Twisting along a curve (in a surface) or along an annulus (in a 3--manifold) is one way to obtain new knots from old. I'll discuss these operations with an eye towards how they affect the bridge number of the knots. Finally, I'll use a new theorem of Baker-Gordon-Luecke to answer several questions from my talk last semester.