Associate Professor and Director of Graduate Admissions

Department of Mathematics

University of Kansas

405 Snow Hall

1460 Jayhawk Boulevard

Lawrence, KS 66045-7594

**Office:** 618 Snow

**Office hours for Spring 2016:** Wednesdays, 2-4pm, or by appointment

**Phone:** (785) 864-7114

**Department fax:** (785) 864-5255

The best way to contact me: send e-mail to

**Teaching** |
**Research** |
**Graduate Admissions** |
**Mathematics Links** |
**Fun Stuff**

I am one of the organizers of the **Great Plains Combinatorics Conference**, to be held at the University of Kansas, May
21-22, 2016.

I am the Vice-Chair of the Kansas Section of the Mathematical Association of America. The University of Kansas will be hosting the 2017 annual meeting, which will take place April 28-29.

**I support the
Kansas Coalition for a Gun Free Campus, which opposes the
legalization of concealed-carry weapons on university campuses. This is
my personal opinion and not the official position of KU or the
Department of Mathematics, although it is shared by Chancellor
Gray-Little, many Distinguished
Professors at KU, and the American
Association of University Professors.**

- Math 725 (Graph Theory), TR 11:00-12:15 PM, Snow 564

- Fall 2016: Math 824 (Algebraic Combinatorics), MWF 1:00-1:50 PM (note change!), Snow 456

- Mathematics competition opportunities for KU students
- If I have agreed to write a
**letter of recommendation**for you, please read this page. - If you are applying to graduate school, here is some advice on writing personal statements (and here is some more).
- Are you an undergrad math major looking for a research experience this summer? Visit MathPrograms.org, the AMS REU website, or Steve Butler's list of REUs.
- Grad school advice and fora: The Grad Cafe, Online PhD, AMS E-Mentoring Blog
- The inside truth: PhD Comics and "What do grad students in math do all day?"

My research interests include combinatorics, algebraic geometry, discrete geometry, and computational commutative algebra. I especially like topics in which these fields intersect: configuration varieties (such as picture spaces of graphs, and Grassmannian, flag, and Schubert varieties), simplicial complexes, Coxeter groups, hyperplane arrangements, Stanley-Reisner theory, matroids, Gröbner bases, and lately Hopf algebras. I am always happy when combinatorial techniques can be used to solve problems from other areas of pure or applied mathematics.

- Curriculum vitae (2/26/16)
- Publications (detailed list with abstracts, talk slides, etc.) (4/21/16)
- Publications (brief list)
- Recent talk slides (2/17/16)
- Source code and data for some research projects and papers

- I have developed (and am perpetually revising) a set of lecture notes for my Algebraic Combinatorics course (Math 824) (last updated 2/18/16). They are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

**Ph.D. students:****Undergraduate honors students:**- Joseph Cummings
- Robert Winslow

- All my past and current students

- KU Combinatorics Group
- KU Combinatorics Seminar (Fridays, 3-4 PM, Snow 408)

- Some of my research, explained in plain English (perennially under construction)
- My talk slides from Red Hot Research on 3/28/14 ("Explain your research program in 6 minutes!")
- My talk about the math of voting at Science on Tap on 3/25/14 (sponsored by KU Natural History Museum and Free State Brewing Co.)
- Materials for "The Notorious Four-Color Problem" (short course at KU Mini College 2013)
- Materials for "Planes, Hyperplanes and Beyond: Understanding Higher-Dimensional Spaces" (short course at KU Mini College 2012)

- Numerical PDE/Geometry/Topology study seminar Fall 2014
- Informal notes on the chip-firing game
- Scribe notes from an informal seminar on Stanley-Reisner theory at the University of Minnesota, Fall 2002
- The Maple worksheet from my talk to the KU Math Club on March 7, 2007 (based on the article "Harmonic algebraic curves and noncrossing partitions"
- Look me up on MathSciNet, the arXiv, or the Math Genealogy Project
- My Erdös number is 2, via John H. Conway and this paper.

- KU Mathematics Department
- KU Combinatorics Seminar
- Combinatorics at KU
- KU Math Seminars and Colloquia
- Open Access at KU

- American Mathematical Society
- Mathematical Association of America and its Kansas Section
- Mathematical Sciences Research Institute
- American Institute of Mathematics
- Simons Foundation
- Canada/USA Mathcamp

- The On-Line Encyclopedia of Integer Sequences
- FindStat (combinatorial statistic finder)
- MacTutor History of Mathematics archive
- Archives of American Mathematics

- Sage (a free, open-source, general-purpose mathematics software system)
- Macaulay 2 (computational commutative algebra and algebraic geometry)
- Polymake and LattE (convex polyhedra, lattice points therein, and finite simplicial complexes)

- arXiv.org e-Print Archive
- A long list of online mathematics resources
- Mathematics on The Simpsons
- AMS Blog: On Teaching and Learning Mathematics

- My bridge page
- Some additional mathematics publications
- Recipes
- XL, a piece of electronic music written by me and remixed by my brother
- How not to be a thesis advisor
- What it's really like to be a graduate student
- The Illustrated Guide to a Ph.D.
- The presumably infamous L'Hopital's Rule warning label
- A photo of me acting like a mathematician

Last updated Sun 4/10/15