Current students

Thursday, February 7, 2019 1:30 pm - 1:30 pm EST (GMT -05:00)

Algebraic Graph Theory Seminar- Caelan Wang

Title: Permutation Problems, Chessboards, and Rook Equivalence

Speaker: Caelan Wang
Affiliation: University of Waterloo
Room: MC 6486

Abstract: We discuss the motivation and development of the theory around rook polynomials.

Wednesday, February 13, 2019 3:30 pm - 3:30 pm EST (GMT -05:00)

Graphs and Matroids Seminar- James Davies ** Rescheduled**

Title: Circle graphs are quadratically x-bounded

Speaker: James Davies
Affiliation: University of Waterloo
Room: **New Room** MC 5501

Abstract: A circle graph $G$ is an intersection graph of a set of chords on a circle.

Friday, February 8, 2019 3:30 pm - 3:30 pm EST (GMT -05:00)

Tutte Colloquium - Jane Gao

Title: The rank of random matrices over finite fields

Speaker: Jane Gao
Affiliation: University of Waterloo
Room: MC 5501

Abstract:

We determine the rank of a random matrix over a finite field with prescribed numbers of non-zero entries in each row and column. As an application we obtain a formula for the rate of low-density parity check codes.

Friday, February 1, 2019 3:30 pm - 3:30 pm EST (GMT -05:00)

Tutte Colloquium - Gabriel Coutinho

Title: Eigenvalue bounds to the (co)clique and chromatic numbers

Speaker: Gabriel Coutinho
Affiliation: Federal University of Minas Gerais, Brazil
Room: MC 5501

Abstract:

This is perhaps one of the oldest topics of interest in spectral graph theory, dating back to the works of Hoffman, Haemers, Delsarte and others, in the 70s.

Friday, February 1, 2019 1:00 pm - 1:00 pm EST (GMT -05:00)

Combinatorial Optimization Reading Group- Rose McCarty

Title: 2-approximation of chromatic number on graph classes excluding a minor

Speaker: Rose McCarty
Affiliation: University of Waterloo
Room: MC 5479

Abstract: In this talk we will see a 2-approximation of the chromatic number of graphs excluding a fixed minor.

Wednesday, January 30, 2019 3:30 pm - 3:30 pm EST (GMT -05:00)

Graphs and Matroids- Tom Kelly

Title: Fractional coloring with local demands

Speaker: Tom Kelly
Affiliation: University of Waterloo
Room: MC 6486

Abstract: In a fractional coloring, vertices of a graph are assigned subsets of the $[0, 1]$-interval such that adjacent vertices receive disjoint subsets. 

Thursday, January 31, 2019 1:30 pm - 1:30 pm EST (GMT -05:00)

Algebraic Graph Theory Seminar- Sabrina Lato

Title: Quantum Walks on Oriented Graphs

Speaker: Sabrina Lato
Affiliation: University of Waterloo
Room: MC 6486

Abstract: A quantum walk on a graph is defined based on a Hermitian matrix associated with the graph, such as the adjacency matrix.

Friday, January 25, 2019 3:30 pm - 3:30 pm EST (GMT -05:00)

Tutte Colloquium - Mehdi Karimi

Title: Convex Optimization Problems in Domain-Driven Form

Speaker: Mehdi Karimi
Affiliation: University of Waterloo
Room: MC 5501

Abstract:

In this talk, we introduce the Domain-Driven form for convex optimization problems and show how general it is by several examples; including LP, SDP, geometric and entropy programming, and quantum entropy optimization.

Friday, January 25, 2019 1:00 pm - 1:00 pm EST (GMT -05:00)

CompOpt Reading Group- Justin Toth

Title: Additive Approximation of Chromatic Number in Apex-minor-free Graphs

Speaker: Justin Toth
Affiliation: University of Waterloo
Room: MC 5479

Abstract: In this talk we will see a t+3 additive approximation to the chromatic number for t-apex-minor-free