Brendan Owens, LSU

Unknotting numbers of knots

Thursday October 6, 4:00PM, Herman Brown 227
The unknotting number of a knot is the number of times you have to pass it through itself to unite it. This seemingly simple invariant is frustratingly difficult to compute. I will describe various approaches to finding these numbers including recent progress using Ozsvath and Szabo's Heegaard Floer theory.