University of Georgia
Department of Mathematics
Seminar Schedule
December 12, 2005
All Seminars are held in Boyd Graduate Studies Bldg. unless otherwise noted.

MONDAY, December 12, 2005

Topology/Geometry
3:15 pm, Room 303
Speaker: Burak Ozbagci (Georgia Tech and Koc University)
Title: Horizontal open books on plumbings
Abstract: I will start with an introduction to Giroux's correspondence between open books and contact structures on 3-manifolds, by giving some elementary examples. Then I will describe a construction of horizontalopen books on oriented circle bundles (with negative Euler number) over oriented closed surfaces and on plumbings of such circle bundles. It turns out the contact structures carried by these open books are horizontal as well. Finally, I will talk about some applications of the construction.
(This is a joint work with Tolga Etgu :
http://front.math.ucdavis.edu/math.GT/0509611 )

Topology/Geometry
4:30 pm, Room 303
Speaker: Paolo Ghiggini (University of Quebec, Montreal)
Title: Tight contact structures with trivial Ozsvath-Szabo invariants
Abstract: We show that infinitely Seifert manifolds over S2 with 4 singular fibres carry infinitely many universally tight contact structures with trivial Ozsvath-Szabo contact invariants. We obtain as a corollary that these contact structures are non weakly symplectically fillable.