Simon Fraser University

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...

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...

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...

Although my talk is arguably about machine-learning, I will use mostly ideas and language from mathematical modelling and numerical analysis. I will introduce a natural geometric learning framework, the atomic cluster expansion (ACE), which focuses...

In this talk we consider the injective chromatic index and the oriented chromatic number of graphs with bounded Euler genus. In particular, we present our proofs of a tight (up to the choice of little o(1)) bound on the injective chromatic index in...

In order to classify certain small generalized hexagons, Cohen and Tits proved that the d-dimensional hypercube has a unique 2-fold cover with no 4-cycles. I will discuss some reasons I find these covers interesting, including a close connection to...

Decomposable abelian varieties, and particularly decomposable Jacobians, have a long history; mainly in the form of formulas to compute hyperelliptic integrals in terms of elliptic ones. The first case where one can have a decomposable Jacobian...

We describe a new form of diagonalization for linear two point constant coefficient differential operators with arbitrary linear boundary conditions. Although the diagonalization is in a weaker sense than that usually employed to solve initial...

In this lecture, I will focus on formulating a dynamical geometric surface partial differential equation for modelling static images during the process of single or collective cell migration. In the absence of detailed experimental molecular and...

Bilevel optimization has been widely used in a variety of areas such as adversarial training, hyperparameter tuning, image reconstruction meta-learning, neural architecture search, and reinforcement learning. In this talk, I will present first-order...