Combinatorial and Algebraic Enumeration
A celebration of Goulden and Jackson's combined 90 years of insight and inspiration that have shaped the fields of algebraic and combinatorial enumeration.
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
Speaker: | Peter Nelson |
Affiliation: | University of Waterloo |
Room: | MC 5417 |
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.
Speaker: | Dinesh Valluri |
Affiliation: | University of Waterloo |
Attend: | Contact Jesse Elliott |
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
Speaker: |
Per Alexandersson |
Affiliation: |
Stockholm University |
Room/Zoom: | MC5479 or for Zoom link contact Logan Crew or Olya Mandelshtam |
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.
To register, click here.
Title: Distance magic labeling on directed graphs
Speaker: |
Alison Marr |
Affiliation: |
Southwestern University |
Zoom: | Contact Sabrina Lato for link |
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
Speaker: | Ronen Wdowinski |
Affiliation: | University of Waterloo |
Room: | MC 5417 |
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 $\lceil (\Delta(G)+1)/2 \rceil$.
Title: Generalized Subspace Subcode with Application in Cryptology
Speaker: | Jean Belo Klamti |
Affiliation: | University of Waterloo |
Attend: | Contact Jesse Elliott |
Abstract:
Most codes with an algebraic decoding algorithm are derived from Reed-Solomon codes. They are obtained by taking equivalent codes, for example Generalized Reed-Solomon codes, or by using the so-called subfield subcode method, which leads to Alternant codes over the underlying prime field, or over some intermediate subfield. The main advantage of these constructions is to preserve both the minimum distance and the decoding algorithm of the underlying Reed-Solomon code.
Title: Virtual characters of permutation statistics
Speaker: | Zachary Hamacker |
Affiliation: | University of Florida |
Room: | MC 5483 |
Abstract:
Functions of permutations are studied in a wide variety of fields including probability, statistics and theoretical computer science. I will introduce a method for studying such functions using representation theory and symmetric functions. As a consequence, one can extract detailed information about asymptotic behavior of many permutation statistics with respect to non-uniform measures that are invariant under conjugation. The key new tool is a combinatorial formula called the path Murnaghan-Nakayama rule that gives the Schur expansion of a novel basis of the ring of symmetric functions. This is joint work with Brendon Rhoades.
Title: Algebraic Graph Theory
Speaker: | Sabrina Lato |
Affiliation: | University of Waterloo |
Location: | MC 6029 |
Abstract:
A graph is distance-regular if we can write the distance adjacency matrices as polynomials in the adjacency matrix. Distance-regular graphs are a class of graphs of significant interest to algebraic graph theorists for their structural and algebraic properties. The notion of distance-regularity can be weakened to a local property on vertices, but when every vertex in the graph is locally distance-regular, the graph will either be distance-regular or in the closely related class of distance-biregular graphs.