Contact Info
Combinatorics & Optimization
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Phone: 519-888-4567, ext 33038
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Thursday, May 26, 2022 — 11:30 AM EDT
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.
Tuesday, May 24, 2022 — 3:00 PM EDT
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.
Tuesday, May 24, 2022 — 9:00 AM to Friday, May 27, 2022 — 4:30 PM EDT
A celebration of Goulden and Jackson's combined 90 years of insight and inspiration that have shaped the fields of algebraic and combinatorial enumeration.
Registration
To register, click here.
Thursday, May 19, 2022 — 1:00 PM EDT
Title: P-partition power sums
| Speaker: | Victor Wang |
| Affiliation: | University of British Columbia |
| Room/Zoom: | MC5479 or for Zoom link contact Logan Crew or Olya Mandelshtam |
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.
Friday, May 13, 2022 — 3:30 PM EDT
Title: Radical Sylvester-Gallai theorem for cubics - and beyond
| Speaker: | Rafael Oliveira |
| Affiliation: | University of Waterloo |
| Location: | MC 5501 or please contact Emma Watson for Zoom link |
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?
Friday, May 13, 2022 — 8:30 AM to Saturday, May 14, 2022 — 5:00 PM EDT
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.
Thursday, May 12, 2022 — 1:00 PM EDT
Title: A vertex model for LLT polynomials and k-tilings of the Aztec diamond
| Speaker: | Andrew Gitlin |
| Affiliation: | UC Berkeley |
| Room/Zoom: | MC5479 or for Zoom link contact Logan Crew or Olya Mandelshtam |
Abstract:
We describe a Yang-Baxter integrable colored vertex model, from which we construct a class of partition functions that equal the LLT polynomials of Lascoux, Leclerc, and Thibon. Using the vertex model formalism, we can prove many properties of these polynomials.
Tuesday, May 10, 2022 — 3:00 PM EDT
Title: Connectivity functions and connectivity intertwining
| Speaker: | Jim Geelen |
| Affiliation: | University of Waterloo |
| Room: | MC 5417 |
Abstract:
Connectivity functions provide a nice way of unifying matroid connectivity with various notions of connectivity in graphs. I will present some new and old open problems.
Monday, May 9, 2022 — 11:30 AM EDT
Title: Polynomials, rank and cap sets
| Speaker: |
Péter Pál Pach |
| Affiliation: |
Budapest University of Technology |
| Zoom: | Contact Sabrina Lato for link |
Abstract:
In this talk we will look at a variant of the polynomial method which was first used to prove that sets avoiding 3-term arithmetic progressions in groups like Z_4^n and F_q^n are exponentially small (compared to the size of the group). We will discuss lower and upper bounds for the size of the extremal subsets. We will also mention some further applications of the method, for instance, the solution of the Erdős–Szemerédi theorem sunflower conjecture.
Friday, April 29, 2022 — 3:00 PM to Sunday, May 1, 2022 — 6:00 PM EDT
DataFest 2022 registration is now OPEN!
All members of your team must register.