Events

The Ontario Combinatorics Workshop is a meeting for researchers working in combinatorics from Ontario and surrounding areas to gather and share their latest research developments. The objective of this meeting is to have an atmosphere conducive to research discussion and collaboration. The setting of the meeting is informal to provide a friendly environment for students and post-doctoral fellows to present their results, to exchange ideas, and to gain exposure to various topics in combinatorics. It is also a place where students and faculties meet, which may foster future collaborations. 

Registration

To register, click here.

Title: Radical Sylvester-Gallai theorem for cubics - and beyond

Abstract:

In 1893, Sylvester asked a basic question in combinatorial geometry: given a finite set of distinct points $v_1, \ldots, v_m \in \R^N$ such that the line defined by any pair of distinct points $v_i, v_j$ contains a third point $v_k$ in the set, must all points in the set be collinear?

Title: P-partition power sums

Abstract:

The Hopf algebra of symmetric functions is spanned by several important bases, including by power sum symmetric functions, which encode the class values of the characters of the symmetric group under the Frobenius characteristic map.

A celebration of Goulden and Jackson's combined 90 years of insight and inspiration that have shaped the fields of algebraic and combinatorial enumeration.

Title: On Donuts and Quasigraphic matroids

Abstract:

Quasigraphic matroids are graph-like objects that give a common generalization of lift and frame matroids. Donuts are edible topological surfaces. I will talk about a surprising link between these two types of object, assuming no prior knowledge of quasigraphic matroids or donuts.

Title: Faster Algorithms for Isogeny Problems using Torsion Point Images. 

Abstract:

In this talk, we will discuss cryptanalysis of some SIDH-type protocols due to Christophe Petit: https://eprint.iacr.org/2017/571.pdf. While finding isogenies between supersingular elliptic curves remains computationally hard to solve, knowledge of images of specific torsion points by the unknown isogeny helps build faster attacks.

Title: Cyclic sieving with focus on open problems

Abstract:

The cyclic sieving phenomenon (CSP) connects a cyclic group action on a family of combinatorial objects with some q-analog of that set. We discuss some recent results and open problems for standard and semistandard tableaux, as well as some other families of combinatorial objects.
Several open problems with various levels of difficulty will be presented.

AlCoVE aims to bring together researchers interested in algebraic combinatorics from around the world. Each talk will be 30 minutes and between talks, there will be casual social activities for spending time with your friends and making new friends. 

To access the Zoom links, you must first register for the conference.

Registration

To register, click here.

Title: Distance magic labeling on directed graphs

Abstract:

This talk will explore two new types of distance magic labelings on directed graphs. Results on some specific classes of directed graphs will be discussed. We will also look at various properties of these two types of labelings and some construction techniques.

Title: Linear arboricity of sparse multigraphs via orientations

Abstract:

The linear arboricity $la(G)$ of a loopless multigraph $G$ is the minimum number of colors required to edge-color $G$ into linear forests, that is, forests whose components are all paths. The Linear Arboricity Conjecture of Akiyama, Exoo, and Harary asserts that the linear arboricity of a simple graph $G$ is at most $\lceil (\Delta(G)+1)/2 \rceil$.