Spring 2010

The KU Combinatorics Seminar meets on **Wednesdays,
3:00--4:00 PM in Snow 408.**
Please contact Jeremy Martin
if you are interested in speaking.

**Wednesday 1/20**

No seminar

**Wednesday 1/27**

Sara Billey (University of Washington)

*A stratification of the space of branched polymers*

**Wednesday 2/3**

No seminar

**Wednesday 2/10**

Jeremy Martin

*Critical groups of graphs and simplicial complexes*

**Wednesday 2/17**

No seminar

**Wednesday 2/24**

No seminar

**Wednesday 3/3**

TBA

**Wednesday 3/10**

Tom Enkosky

*Slope Varieties and Series-Parallel Networks*

**Wednesday 3/17**

No seminar -- Spring Break

**Wednesday 3/24**

Brandon Humpert

*The Chromatic Hopf Algebra of Graphs*

**Wednesday 3/31**

No seminar

**Wednesday 4/7**

No seminar

**Wednesday 4/14**

Hailong Dao

*Cluster Algebras*__Abstract:__This talk will be an elementary introduction into cluster algebras. They are strangely defined (by Fomin-Zelevinsky) combinatorial/algebraic objects, but somehow find their way into a variety of areas such as quiver representations and Calabi-Yau algebras.

**Wednesday 4/21**

No seminar

**Wednesday 4/28**

Brandon Humpert

*The Gebhard-Sagan noncommutative chromatic symmetric function*

**Wednesday 5/5**

Lucas Sabalka (Binghamton University)

*F-Vectors of Subdivided Simplicial Complexes*__Abstract:__Brenti and Welker have shown that for any simplicial n-dimensional complex X, the f-vectors of successive barycentric subdivisions of X have roots which converge to fixed values depending only on the dimension of X. In this talk, we will present this result, sketching a new, simple, and intuitive geometric proof. Moreover, we will discuss generalizations of this result, computations of these limit values, and show an interesting symmetry of the limit values about the real number -2. This is based on joint work with Emanuele Delucchi and Aaron Pixton.

Jeremy Martin's home page

Last updated Wed 4/28/10