Dear Topologists and Friends of Topology, The topology seminar tomorrow (MSCS 514 at 3:30) will be by Ken Baker from the University of Miami.

Title: On non-looseness of non-loose knots

Abstract: A contact structure on a 3-manifold is called overtwisted if there is a certain kind of embedded disk called an overtwisted disk; it is tight if no such disk exists. A Legendrian knot in an overtwisted contact 3-manifold is loose if its complement is overtwisted and non-loose if its complement is tight. We define and compare two geometric invariants, depth and tension, that measure how far from loose is a non-loose knot. This is joint work with Sinem Onaran.