The C&O department has 36 faculty members and 60 graduate students. We are intensely research oriented and hold a strong international reputation in each of our six major areas:
- Algebraic combinatorics
- Combinatorial optimization
- Continuous optimization
- Cryptography
- Graph theory
- Quantum computing
Read more about the department's research to learn of our contributions to the world of mathematics!
News
Three C&O faculty win Outstanding Performance Awards
The awards are given each year to faculty members across the University of Waterloo who demonstrate excellence in teaching and research.
Prof. Alfred Menezes is named Fellow of the International Association for Cryptologic Research
The Fellows program, which was established in 2004, is awarded to no more than 0.25% of the IACR’s 3000 members each year and recognizes “outstanding IACR members for technical and professional contributions to cryptologic research.”
C&O student Ava Pun receives Jessie W. H. Zou Memorial Award
She received the award in recognition of her research on simulating virtual training environments for autonomous vehicles, which she conducted at the start-up Waabi.
Events
Tutte colloquium-R. Tyrell Rockafellar
Title: Problem Decomposition in Optimization: Algorithmic Advances Beyond ADMM
Speaker: | R. Tyrell Rockafellar |
Affiliation: | The University of Washington |
Location: | Main Hall, Federation Hall |
Abstract:
Decomposition schemes like those coming from ADMM typically start by posing a separable-type problem in the Fenchel duality format. They then pass to an augmented Lagrangian, which however can interfere with the separability and cause a slow-down. Progressive decoupling offers a more flexible approach which can utilize augmented Lagrangians while maintaining decomposability. Based on a variable metric extension of the proximal point algorithm that's applied in a twisted sort of way, progressive decoupling benefits from stopping criteria which can guarantee convergence despite inexact minimization in each iteration. The convergence is generically at a linear rate, and for convex problems, is global. But the method also works for nonconvex problems when initiated close enough to a point that satisfies a natural extension of the strong sufficient condition for local optimality known from nonlinear programming.
This talk is held as part of the 26th Annual Midwest Optimization Meeting (“MOM26”).
Tutte colloquium-Guoyin Li
Title: Proximal methods for nonsmooth and nonconvex fractional programs: when sparse optimization meets fractional programs
Speaker: | Guoyin Li |
Affiliation: | University of New South Wales |
Location: | MC 5501 |
Abstract:Nonsmooth and nonconvex fractional programs are ubiquitous and also highly challenging. It includes the composite optimization problems studied extensively lately, and encompasses many important modern optimization problems arising from diverse areas such as the recent proposed scale invariant sparse signal reconstruction problem in signal processing, the robust Sharpe ratio optimization problems in finance and the sparse generalized eigenvalue problem in discrimination analysis.
In this talk, we will introduce extrapolated proximal methods for solving nonsmooth and nonconvex fractional programs and analyse their convergence behaviour. Interestingly, we will show that the proposed algorithm exhibits linear convergence for the scale invariant sparse signal reconstruction model, and the sparse generalized eigenvalue problem with either cardinality regularization or sparsity constraints. This is achieved by identifying the explicit desingularization function of the Kurdyka-Ł ojasiewicz inequality for the merit function of the fractional optimization models. Finally, if time permits, we will present some preliminary encouraging numerical results for the proposed methods for sparse signal reconstruction and sparse Fisher discriminant analysis
The talk is based on joint work with R.I. Bo ̧t, M. Dao, T.K. Pong and P. Yu.
Algebraic and enumerative combinatorics seminar-Colleen Robichaux
Title:Vanishing of Schubert coefficients
Speaker | Colleen Robichaux |
Affiliation | UCLA |
Location | MC 5479 |
Abstract: Schubert coefficients are nonnegative integers that arise in Algebraic Geometry and play a central role in Algebraic Combinatorics. It is a major open problem whether they have a combinatorial interpretation, i.e, they are in #P. In this talk we discuss the closely related problem of the vanishing of Schubert coefficients. We prove that this vanishing problem is rather low in the polynomial hierarchy and discuss implications of this result.
This is joint work with Igor Pak.
There will be a pre-seminar presenting relevant background at the beginning graduate level starting at 1pm,