Contact Info
Combinatorics & Optimization
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Phone: 519-888-4567, ext 33038
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Welcome to Combinatorics and Optimization
Tutte's Distinguished Lecture Series
The very successful Tutte's 100th Distinguished Lecture Series has now completed. That success has led to a Tutte Distinguished Lecture once per term. The next lecture will happen in the Spring term.
*Recordings of occurred talks are all available on C&O's YouTube Channel.
Grad Studies: Fall 2020 applications now open
New Deadline: February 1, '20
News
- May 5, 2021C&O welcomes its two newest faculty members
Olya Mandelshtam and Kanstantsin Pashkovich are the newest faculty members in the C&O department.
- May 4, 2021Fields Institute workshops organized by Henry Wolkowicz
Professor Henry Wolkowicz is a co-organizer of an upcoming Workshop on Discrete Geometry, Semidefinite Programming and Applications (May 10-14) and a Mini-Symposium on Sensor Network Localization and Dynamical Distance Geometry (May 18-27).
- Apr. 27, 2021Sophie Spirkl's work featured in Quantamagazine
In her paper, the 1989 Erdos-Hajnal conjecture is resolved for cycles of length 5.
Events
- May 17, 2021Algebraic Graph Theory Seminar - Bojen Mohar
Title: Minimum eigenvalue of nonbipartite graphs
Speaker: Bojan Mohar Affiliation: Simon Fraser University Zoom: Contact Soffia Arnadottir Abstract:
Let \rho and \lambda be the largest and the smallest eigenvalue of a connected graph G. It is well-known that \rho + \lambda \geq 0 and that equality occurs if and only if G is bipartite. The speaker will discuss what else can we say when G is not bipartite.
- May 20, 2021Algebraic Combinatorics Seminar - Steven Karp
Title: q-Whittaker functions, finite fields, and Jordan forms
Speaker: Steven Karp Affiliation: UQAM Zoom: Contact Steve Melczer Abstract:
The q-Whittaker symmetric function associated to an integer partition is a q-analogue of the Schur symmetric function. We give a new formula for the q-Whittaker function in terms of partial flags compatible with a nilpotent endomorphism over the finite field of size 1/q.
- May 21, 2021Tutte Colloquium - Steve Melczer
Title: Positivity Problems for Linear Recurrences
Speaker: Steve Melczer Affliliation: University of Waterloo Zoom: Contact Emma Watson Abstract:
Although sequences satisfying linear recurrence relations have been studied for centuries, and appear as some of the first examples of combinatorial sequences encountered in an introductory combinatorics class, there are natural examples of simply stated problems related to their basic behaviour whose decidability is unknown. In this talk we survey some open computability and complexity questions related to the positivity of linearly recurrent sequences, before examining a new approach to proving positivity using rigorous numerical methods for functions satisfying linear differential equations.