## Seminars and Colloquia by Series

Monday, December 4, 2017 - 14:00 , Location: Skiles 006 , Soren Galatius , Stanford University , Organizer: Kirsten Wickelgren
Monday, November 20, 2017 - 14:05 , Location: Skiles 006 , Kevin Kordek , Georgia Institute of Technology , Organizer: Dan Margalit
Monday, November 13, 2017 - 13:55 , Location: Skiles 006 , Thang Le , Georgia Tech , , Organizer: Thang Le
Monday, November 6, 2017 - 13:55 , Location: TBA , Peter Lambert-Cole and Alex Zupan , Georgia Tech and Univ. Nebraska Lincoln , Organizer: Caitlin Leverson
Monday, October 30, 2017 - 13:55 , Location: Skiles 006 , Shea Vela-Vick , LSU , Organizer: John Etnyre
Thursday, October 26, 2017 - 11:00 , Location: TBA , Nikita Selinger , University of Alabama-Birmingham , Organizer: Balazs Strenner
Monday, October 23, 2017 - 13:55 , Location: Skiles 006 , Mark Hughes , BYU , Organizer: John Etnyre
The immersed Seifert genus of a knot $K$ in $S^3$ can be defined as the minimal genus of an orientable immersed surface $F$ with $\partial F = K$.  By a result of Gabai, this value is always equal to the (embedded) Seifert genus of $K$.  In this talk I will discuss the embedded and immersed cross-cap numbers of a knot, which are the non-orientable versions of these invariants.  Unlike their orientable counterparts these values do not always coincide, and can in fact differ by an arbitrarily large amount.  In further contrast to the orientable case, there are families of knots with arbitrarily high embedded 4-ball cross-cap numbers, but which are easily seen to have immersed cross-cap number 1.  After describing these examples I will discuss a classification of knots with immersed cross-cap number 1.  This is joint work with Seungwon Kim.
Monday, October 16, 2017 - 13:55 , Location: Skiles 006 , Kyle Hayden , Boston College , Organizer: John Etnyre
Every four-dimensional Stein domain has a Morse function whoseregular level sets are contact three-manifolds. This allows us to studycomplex curves in the Stein domain via their intersection with thesecontact level sets, where we can comfortably apply three-dimensional tools.We use this perspective to understand links in Stein-fillable contactmanifolds that bound complex curves in their Stein fillings.
Monday, October 9, 2017 - 13:55 , Location: Skiles 006 , None , None , Organizer: Jennifer Hom
Monday, October 2, 2017 - 15:30 , Location: Skiles 005 , Jeff Meier , UGA , Organizer: Caitlin Leverson
I'll introduce you to one of my favorite knotted objects: fibered, homotopy-ribbon disk-knots.  After giving a thorough overview of these objects, I'll discuss joint work with Kyle Larson that brings some new techniques to bear on their study.  Then, I'll present new work with Alex Zupan that introduces connections with Dehn surgery and trisections.  I'll finish by presenting a classification result for fibered, homotopy-ribbon disk-knots bounded by square knots.