Contact Info
Combinatorics & Optimization
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Phone: 519-888-4567, ext 33038
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Thursday, May 31, 2018 3:30 PM EDT
Title: Counting biased cliques
| Speaker: | Peter Nelson |
| Affiliation: | University of Waterloo |
| Room: | MC 5479 |
Abstract: A biased graph is a pair consisting of an undirected graph G,
Thursday, May 31, 2018 11:30 AM EDT
Title: A single pass bijection between certain quarter plane lattice walks and certain Motzkin-like paths.
| Speaker: | Karen Yeats |
| Affiliation: | University of Waterloo |
| Room: | MC 6486 |
Abstract: A p-tandem quarter plane walk is a walk starting at the origin and remaining in the first quadrant
Friday, May 25, 2018 3:30 PM EDT
Title: Combinatorics in Particle Interactions
| Speaker: | Freddy Cachazo |
| Affiliation: | Perimeter Institute |
| Room: | MC 5501 |
Abstract:
The main approach for testing physical theories of particles is via scattering experiments. The traditional approach for computing theoretical predictions uses Feynman diagrams.
Friday, May 25, 2018 9:00 AM EDT
Title: Miniconference on combinatorial structures in perturbative QFT 2: transforms and graph counting
| Speakers: |
various |
Thursday, May 24, 2018 3:30 PM EDT
Title: Finding Independent Transversals Efficiently
| Speaker: | Alessandra Graf |
| Affiliation: | University of Waterloo |
| Room: | MC 5479 |
Abstract: Let G be a graph whose vertex set is partitioned into classes V1,..., Vm. An independent transversal of G with respect to (V1,...,Vm) is an independent set {v1,...,vm} in G such that vi is in Vi for each i.
Thursday, May 24, 2018 1:30 PM EDT
Title: Graph Reconstruction
| Speaker: | Cathy Wang |
| Affiliation: | University of Waterloo |
| Room: | MC 6486 |
Abstract: The graph reconstruction conjecture by Kelly and Ulam states that all graphs on at least three vertices are determined by their one-vertex deleted subgraphs, up to isomorphism.
Thursday, May 24, 2018 11:30 AM EDT
Title: Asymptotics of the principal of specializations of Schubert polynomials
| Speaker: | Alejandro Morales |
| Affiliation: | University of Massachusetts Amherst |
| Room: | MC 6486 |
Abstract: Schubert polynomials were introduced by Lascoux and Sch\"utzenberger in 1982 to study Schubert varieties.
Friday, May 18, 2018 3:30 PM EDT
Title: The number theory of equiangular lines
| Speaker: | Jon Yard |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract:
It is easy to prove that there can exist at most d2 equiangular complex lines in Cd. Configurations saturating this bound are known by other names: maximal equiangular tight frames, minimal complex projective 2-designs and symmetric informationally complete positive operator-valued measures (SIC-POVMs).
Thursday, May 17, 2018 3:30 PM EDT
Title: Representability of Matroids
| Speaker: | Rutger Campbell |
| Affiliation: | University of Waterloo |
| Room: | MC 5479 |
Abstract: I will go over some negative results regarding characterizations for the class of representable
Thursday, May 17, 2018 1:30 PM EDT
Title: The Combinatorial Nullstellensatz
| Speaker: | Maxwell Levit |
| Affiliation: | University of Waterloo |
| Room: | MC 6486 |
Abstract: I will survey Alon's survey of the combinatorial nullstellensatz.
Thursday, May 17, 2018 11:30 AM EDT
Title: Asymptotic Distribution of Parameters in Random Maps
| Speaker: | Julien Courtiel |
| Affiliation: | Universite de Caen in France |
| Room: | MC 6486 |
Abstract: A rooted map is a connected graph
Friday, May 11, 2018 3:30 PM EDT
Title: Large matroids: asymptotic enumeration
| Speaker: | Jorn van der Pol |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract:
How many matroids are there on a ground set of a given size? Although the question is a very basic one, we only know the answer up to a constant factor in the exponent.
Thursday, May 10, 2018 3:30 PM EDT
Title: Coloring Graphs of Bounded Maximum Degree with Small Clique Number
| Speaker: | Tom Kelly |
| Affiliation: | University of Waterloo |
| Room: | MC 5479 |
Abstract: Greedy coloring yields an upper bound on the chromatic number $\chi$ of $\Delta+1$ for graphs of maximum degree at most $\Delta$, which is tight for cliques.
Thursday, May 10, 2018 1:30 PM EDT
Title: The Number 6 Hash Function Collision
| Speaker: | Chris Godsil |
| Affiliation: | University of Waterloo |
| Room: | MC 6486 |
Abstract: If V is a vector space of dimension d over the eld GF(q), we have all sorts of families of
Monday, May 7, 2018 1:00 PM EDT
Title: LWE part 3: The relation with BDD
| Speaker: | Luis Ruiz |
| Affiliation: | University of Waterloo |
| Room: | MC 6486 |
Abstract: The last piece of the puzzling reduction
Friday, May 4, 2018 3:30 PM EDT
Title: The combinatorics of Standard Young tableaux of bounded height
| Speaker: | Marni Mishna |
| Affiliation: | Simon Fraser University |
| Room: | MC 5501 |
Abstract:
Standard Young tableaux are a classic object of mathematics, appearing in problems from representation theory to bijective combinatorics.
Thursday, May 3, 2018 11:30 AM EDT
Title: An elementary approach to the quasipolynomiality of the Kronecker coefficients