I have been part of the math
department at the University of Western Ontario since 2002. I
received my PhD at the University
of Michigan in 1999.
Research
I am interested in a mix of combinatorics, geometry, and algebra.
That includes algebraic and topological
aspects of matroid theory, and arrangements of hyperplanes. I like to
use techniques from algebraic geometry and commutative algebra in
combinatorial settings.
I have some preprints and publications available here.
Teaching
Winter 2023:
- Math 1120B, Fundamental Concepts in Mathematics
Other Activities
Conference and workshop organization:
Past events:
- Arrangements at Home, a three-part online conference on
recent developments in arrangement theory, summer 2020. Coorganized with
Christin Bibby (Louisiana
State University)
and Alex Suciu (Northeastern).
-
Workshop on Polyhedral Products in Homotopy Theory Fields
Institute, Toronto, 20-24 January 2020. Coorganized with Tony Bahri (Rider University) and Jelena Grbic (Southampton).
- Arrangements at
Western, May 21-31 2019. This included a workshop (May 23-25). Co-organized with Alex Suciu and
Christin Bibby.
- Arrangements
of Hypersurfaces, a one-day workshop (April 20th 2018) and an AMS special session at the 2018 Spring Eastern
Meeting, April 21-22, 2018, Northeastern University, Boston, MA. Coorganized
with Alex Suciu.
-
Topology of
Arrangements and Representation Stability, Oberwolfach, 14-20
January 2018, coorganized with Giovanni Gaiffi (Pisa), Rita Jimenez
Rolland (Oaxaca), and
Alex Suciu (Boston).
- CAAC 2016, Western, 22-24 January
2016, coorganized with Nicole
Lemire
(Western) and Hugh Thomas (UQAM), a three-day meeting in algebraic
combinatorics and its interactions with algebraic geometry and
commutative algebra. (The abstracts
page has slides from some of the talks.)
- Combinatorial
Constructions in Topology, University of Regina, August 17-21,
2015, coorganized
with Soumen Sarkar, Don Stanley (U. Regina) and Alex Suciu
(Northeastern University). See the abstracts page for slides
from some of the talks.
- Differential
and Combinatorial Aspects of Singularities, TU Kaiserslautern,
coorganized with Mathias
Schulze, Christian
Sevenheck, Uli
Walther, August 3-7, 2015. See the abstracts page for the slides
from some of the talks.
- Computational
Geometric Topology in Arrangement Theory, ICERM (Providence, RI),
July 6-10, 2015, with Nero Budur, Dani Matei, Laurentiu Maxim, Hal
Schenck, and Max Wakefield.
- A focussed research group
Hyperplane Arrangements, Wonderful Compactifications, and
Tropicalization
at BIRS, with June
Huh
and Alex Suciu,
April 2014.
- Cohomology
Rings and
Fundamental Groups of Hyperplane Arrangements, Wonderful
Compactifications, and Real Toric Varieties at the Mathematisches
Forschungsinstitut Oberwolfach, with Alex Suciu, October
2012.
- An AMS special session "The Algebraic Geometry
and
Topology of
Hyperplane Arrangements" at the AMS
spring sectional meeting in Worcester, MA, April 9-10, 2011,
preceded by
a workshop at Northeastern University on April 8, with Alex Suciu.
- A Conference
in Honour of Peter Orlik at the Fields Institute in Toronto,
with Dan Cohen
and Nicole Lemire,
August 2008.
I am a fan of Macaulay
2 (software for commutative algebra and algebraic geometry). Greg Smith
and I have written a package for computation with hyperplane
arrangements. It is included with the standard Macaulay 2
distribution (versions ≥ 1.0).
I was on sabbatical from July 2016 -- June 2017: I visited the University of Sydney from January through April, and ALTA at the University of Bremen from May through July. During my previous sabbatical in 2009--10, I visited
the EPFL (Lausanne) from September
through November, and the University
of
Oregon from January through summer 2010.