Slides from some of my talks

1. Permutations, card shuffling and representation theory, CUMC/CCEM 2013 (slides).
2. Down operators on the affine nilCoxeter algebra and expansions of noncommutative k-Schur functions (with Chris Berg and Luis Serrano). FPSAC 2012 (poster).
3. Primitive orthogonal idempotents for R-trivial monoids (with Chris Berg, Nantel Bergeron, Sandeep Bhargava). FPSAC 2011 (poster).
4. Pourquoi Sage est-elle si cool? (IGM-MLV, France, November 2008). Abstract, Slides and Worksheets.

   • Slides: pdf
   • Getting Help: worksheet, pdf
   • Interfaces: worksheet, pdf
   • Combinatorics: worksheet, pdf
   • Symmetric Functions: worksheet, pdf
   • Cython: worksheet, pdf
   • Words: worksheet, pdf

   Cette présentation sera une introduction à Sage, et mon objectif et de vous convaincre que Sage est un excellent système pour la recherche en mathématiques. Un extrait du tutoriel Sage: "Sage est un logiciel mathématique libre destiné à la recherche et à l'enseignement en algèbre, géométrie, arithmétique, théorie des nombres, cryptographie, calcul scientifique et dans d'autres domaines apparentés. ... Le but général de Sage est de créer une alternative libre viable à Maple, Mathematica, Magma et MATLAB" et MuPAD. Je vais présenter l'histoire du projet et je vais donner une démonstration. Nous nous concentrerons sur la combinatoire, et en particulier sur le projet "sage-words", du logiciel pour faire la combinatoire des mots avec Sage.

5. Posets and words in Sage-Combinat (Sage Days 10, Nancy, France, October 2008).
6. Some very cool things about Sage (LaCIM/UQAM, March 2008). Abstract, LaTeX.

   This talk is an introduction to the free, open-source mathematics software Sage. The overall goal of Sage is to create a viable, free, open-source alternative to Maple, Mathematica, Magma and MATLAB. In this talk I will explain why I am really excited about the project. The demonstrations will focus specifically on doing combinatorics in Sage.

7. A Very, Very Special Class of Algebras (Zacatecas, May 2007). Abstract.

   Ten reasons that an algebra arising from a quiver with relations associated to a hyperplane arrangement is interesting. These turn out to be Koszul algebras, which justifies the title. (Ed Green gave a talk on Koszul algebras entitled A very special class of algebras.) The talk was presented at the AMS-SMM special session in honour of Ed Green's 60th birthday.

8. The Geometric Approach to the Descent Algebra (UQAM, October 2006). Abstract.

   Slides from my talk at the LaCIM seminar describing what I call the "geometric approach" to the descent algebra. This approach identifies the descent algebra with a subalgebra of a semigroup algebra constructed from the faces of a hyperplane arrangement.

9. Slides from my thesis defence (Cornell, May 2006).
10. Geometry and Algebra of Hyperplane Arrangements (CMS Meeting, December 2005). Abstract.

    Slides from a talk given at the 2005 CMS Winter meeting at the University of Waterloo.