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Please note: The University of Waterloo is closed for all events until further notice.

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

  1. May 5, 2021C&O welcomes its two newest faculty members
    Tutte square

    Olya Mandelshtam and Kanstantsin Pashkovich are the newest faculty members in the C&O department.

  2. May 4, 2021Fields Institute workshops organized by Henry Wolkowicz
    Field Institute

    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).

  3. Apr. 27, 2021Sophie Spirkl's work featured in Quantamagazine

    In her paper, the 1989 Erdos-Hajnal conjecture is resolved for cycles of length 5.

Read all news
  1. 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


    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.

  2. 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


    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.

  3. May 21, 2021Tutte Colloquium - Steve Melczer

    Title: Positivity Problems for Linear Recurrences

    Speaker: Steve Melczer
    Affliliation: University of Waterloo
    Zoom: Contact Emma Watson


    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.

All upcoming events