Past Events
Scientific, Seminar
PIMS-CORDS SFU Operations Research Seminar: Betty Shea
November 14, 2024
Simon Fraser University
The practical performance of an optimization method depends on details such as using good step sizes. Strategies for setting step sizes are generally limited to hyperparameter tuning (for a fixed step size), step size schedules and line searches. For...
Scientific, Seminar
UVictoria Discrete Math Seminar: Christopher Duffy
November 14, 2024
University of Victoria
In defining colouring of oriented graphs via homomorphism one finds an easily checkable necessary condition for a valid colouring — vertices at directed distance at most two must receive different colours. With this idea in mind we extend the...
Scientific, Seminar
UW Combinatorics and Geometry Seminar: Foster Tom
November 13, 2024
University of Washington
We prove a new signed elementary symmetric function expansion of the chromatic symmetric function. We then use sign-reversing involutions to prove e -positivity for graphs formed by joining cycles or cliques at single vertices. By considering...
Scientific, Seminar
L-functions in Analytic Number Theory Seminar: Valeriya Kovaleva
November 12, 2024
Online
In this talk we will discuss the behaviour of the Riemann zeta on the critical line, and in particular, its correlations in various ranges. We will prove a new result for correlations of squares, where shifts may be up to size T3/2-ε. We will also...
Scientific, Seminar
SFU Mathematics of Computation, Application and Data ("MOCAD") Seminar: Nicolas Boullé
November 8, 2024
Simon Fraser University
Operator learning is an emerging field at the intersection of machine learning, physics, and mathematics, that aims to discover properties of unknown physical systems from experimental data. Popular techniques exploit the approximation power of deep...
Scientific, Seminar
UBC Number Theory Seminar: Emily Quesada-Herrera
November 8, 2024
University of British Columbia
In 1973, assuming the Riemann hypothesis (RH), Montgomery studied the vertical distribution of zeta zeros, and conjectured that they behave like the eigenvalues of some random matrices. We will discuss some models for zeta zeros - starting from the...
Scientific, Seminar
05C50 Online Seminar: Shaun Fallat
November 8, 2024
Online
Let us ask: What is a "strong" matrix property and why is such a property useful for studying eigenvalues of graphs? During this talk we will attempt to address both questions above by first wandering through some of the developed strong matrix...
Scientific, Seminar
PIMS-CORDS SFU Operations Research Seminar: Nitya Mani
November 7, 2024
Simon Fraser University
An $H$-intersecting family of 3-uniform hypergraphs on $n$ labelled vertices is a family of hypergraphs $\mathcal{F}$ such that for any pair of hypergraphs $G_1, G_2 \in \mathcal{F}$, the intersection $G_1 \cap G_2$ contains a copy of $H$ as a...
Scientific, Seminar
UVictoria Discrete Math Seminar: Shivaramakrishna Pragada
November 7, 2024
University of Victoria
Let $G$ be a graph with $n$ vertices. Let $A(G)$ be its adjacency matrix. Let $\lambda_1(G), \lambda_2(G)$ denote the largest and second largest eigenvalues of the adjacency matrix. Bollob\'{a}s and Nikiforov (2007) conjectured that for any graph $G...
Scientific, Seminar
URegina Topology and Geometry Seminar: Adela YiYu Zhang
November 7, 2024
Online
The synthetic analogue of the bar comonad controls the universal differentials in the bar spectral sequence of algebras over spectral operads. This can be viewed as a deformation of Koszul duality of such algebras. I will explain ongoing work with...