Simon Fraser University

We will characterize members that maximize/minimize the second largest adjacency eigenvalue in certain families of trees. Joint work with H. Kumar, B. Mohar and S. Pragada.

We consider covering graphs obtained by lifting trees as voltage graphs over cyclic groups. We generalize a tool of Hell, Nishiyama, and Stacho, known as the billiard strategy, for constructing Hamiltonian cycles in the covering graphs of paths. The...

Sharpness is a generic assumption in continuous optimization that bounds the distance to the set of minimizers in terms of the suboptimality in the objective function. It leads to the acceleration of first-order optimization methods via so-called...

The defining property of fine moduli stacks (of curves) is that they have 'universal families' which translates the study of a family of (curves) as the study of morphisms to moduli stacks. I will explain this idea using Hom_{n}(P^1, Mbar_{1,1}) the...

The Coast Combinatorics Conference Series began in 1999. In most years there has been a meeting on the Canadian west coast in February or March, featuring a collegial, collaborative, workshop-style atmosphere and a diverse collection of talks on...

In his seminal work on modular curves and the Eisenstein ideal, Mazur studied the existence of congruences between certain Eisenstein series and newforms, proving that Eisenstein ideals associated to weight 2 cusp forms of prime level are locally...

In this talk, we will study the mean field limit of weakly interacting diffusions for confining and interaction potentials that are not necessarily convex. We explore the relationship between the large N limit of the constant in the logarithmic...

In a proportional contact representation of a planar graph, each vertex is represented by a simple polygon with area proportional to a given weight, and edges are represented by adjacencies between the corresponding pairs of polygons. We show how to...

I will describe a new approach for exhaustively generating combinatorial objects by combining a satisfiability (SAT) solver with an isomorph-free exhaustive generation method such as orderly generation. The SAT solver is able to limit the search to...

Motivated by an application in the routing of technicians at a French public utility, we introduce a highly efficient heuristic together with a branch-price-and-cut algorithm for the doubly open park-and-loop routing problem. This problem is an...