The Informal Symplectic Geometry Seminar meets 9:30-10:30am in Math 520 on Fridays. The Informal Symplectic Geometry Seminar should not be confused with Columbia's more traditional Symplectic Geometry and Gauge Theory seminar.

Previous semesters: Spring 2009, Fall 2008, Spring 2008, Fall 2007.

ISG seminar schedule. (iCal)
Date Speaker Title

Sept. 18

Peter Horn (Columbia) Knot concordance and gropes

Sept. 25

Oct. 2

Oct. 9

Oct. 16

Oct. 23

Oct. 30

Nov. 6

Nov. 13

Nov. 20

Nov. 27

Dec. 4

Dec. 11

 

Abstracts.

September 18, 2009.

Peter Horn (Columbia), "Knot concordance and gropes"

Abstract: In the late 90s, Cochran, Orr and Teichner introduced two filtrations of the knot concordance group. I will discuss the grope filtration of the knot concordance group and some invariants that are generalizations of the slice genus of a knot. I will discuss some of the constructions and obstructions in this corner of knot theory.

 

Other relevant information.

Our e-mail list.

Announcements for this seminar, as well as for related seminars and events, are sent to the "Floer Homology" e-mail list maintained via Google Groups. You can subscribe directly via Google Groups or by contacting R. Lipshitz.