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 Combinatorics and Optimization graduate students receive $120,000 as part of the federal government’s CRTAS program
Current Combinatorics and Optimization PhD students Cece Henderson, Nic Swanson and Ben Wong each received a Canada Graduate Research Scholarship – Doctoral (CGRS D). Valued at $40,000 per year, the scholarship runs for three years.
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.
Sina Kalantarzadeh wins Governor General's Gold Medal
The Governor General’s Gold Medal is one of the highest student honours awarded by the University of Waterloo.
Events
Crypto Reading Group on quantum computing | Douglas Stebila, QKD Security
| Speaker: | Douglas Stebila |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract: Having seen the BB84 quantum key distribution protocol last week, this week we’ll see what it means for QKD to be secure, following the basic principle that “information gain implies disturbance”. We’ll talk about what authentication is needed for QKD’s security guarantees to hold, and other factors like device security and finite key effects.
Algebraic and Enumerative Combinatorics Seminar | Shao Yuan Lin, Distinguishability and linear independence for H-chromatic symmetric functions
| Speaker: | Shao Yuan Lin |
| Affiliation: | University of Waterloo |
| Location: | MC 5417 |
Abstract: We study the H-chromatic symmetric functions X_G^H introduced by Eagles et al. (2022), which generalizes the chromatic symmetric function X_G to the context of H-colorings, which tracks graph homomorphisms G → H. We first show that self-chromatic symmetric functions X_G^G determine quantities like the connected components of a forest and the degree sequence of a caterpillar. We then show that the X_G^H's form a basis of the symmetric function ring for certain collections of (G,H), such as the self-CSFs of complete multipartite graphs. Lastly, we define and discuss H-chromatic polynomials as specializations of H-CSFs. This is joint work with Laura Pierson.
There will be a pre-seminar presenting relevant background at beginning graduate level starting at 1:30pm in MC 5417.
Tutte Colloquium | Bertrand Guenin, Integral Set Packing versus Integral Set Covering
| Speaker: | Bertrand Guenin |
| Affiliation: | University of Waterloo |
| Location: | MC 5501 |
Abstract: A 0-1 matrix M is perfect if the polyhedron {x ≥ 0 : Mx ≤ 1} is integral. Perfect matrices are closely related to perfect graphs and have several remarkable properties. In particular, perfectness is equivalent to total dual integrality, and perfect matrices admit an excluded-minor characterization.
A 0-1 matrix M is ideal if the polyhedron {x ≥ 0 : Mx ≥ 1} is integral. Unlike perfect matrices, ideal matrices do not correspond to a single well-understood class of combinatorial objects. In this talk, we will explore which of the remarkable properties of perfect matrices have counterparts for ideal matrices. We will discuss what is known, what fails, and some of the intriguing open questions that arise from this comparison.
