Title: Resilience of the rank of random matrices
| Speaker: | Jorn van der Pol |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract:
I will discuss the preprint of this title by Ferber, Luh, and McKinley (arXiv:1910.03619).
Title: Incompressibility of classical distributions
| Speaker: | Debbie Leung |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract:
We prove a general, robust, single-letter lower bound on the achievable rate for ensembles of classical states, which holds even when Alice and Bob share free entanglement and allow a constant local error.
Title: How can we optimize nonsmooth objectives globally?
| Speaker: | Andreas Griewank |
| Affiliation: | Humboldt University, Germany |
| Room: | MC 5501 |
Abstract:
In machine learning objective functions that are only piecewise smooth and should be globally minimized abound. The standard method of dealing with them is to apply a stochastic gradient method disregarding the rare points of nonsmoothness and hoping for the best as far as global optimality of the computed solution is concerned.
Title: Inverses of Trees
| Speaker: | Krystal Guo |
| Affiliation: | Centre de Recherches Mathématiques & Université de Montréal |
| Room: | MC 5417 |
Abstract:
A tree is invertible if and only if it has a perfect matching.
Godsil considers an invertible tree T and finds that the inverse of the adjacency matrix has entries in {0, ±1} and is the signed adjacency matrix of a graph which contains T.
Title: Biometric security: Design, implementation, and challenges
| Speaker: | Koray Karabina |
| Affiliation: | Florida Atlantic University |
| Room: | MC 5501 |
Abstract:
Biometric based cybersecurity technologies offer significant advantages in authentication, identification, and access control mechanisms.
Title: Graph covers with two new eigenvalues
| Speaker: | Olha Silina |
| Affiliation: | University of Waterloo |
| Room: | MC 5479 |
Abstract:
I am going to talk about graph covers. If $Y$ is a cyclic cover of $X$, it turns out that $Y$ has the same spectrum as $X$ plus (possibly) some new eigenvalues.
Title: OutFn, M_gn and renormalized topological field theory
| Speaker: | Michael Borinsky |
| Affiliation: | Nikhef |
| Room: | MC 5417 |
Abstract:
I will report on recent joint work with Karen Vogtmann on the Euler characteristic of Out(F_n) and the moduli space of graphs.
Title: Periodicity in Quantum Walks
| Speaker: | Chris Godsil |
| Affiliation: | University of Waterloo |
| Room: | MC 5417 |
Abstract:
Despite the title, quantum walks are, in general, not periodic. However they are, in general, periodic to any desired degree of accuracy.
Title: Beating 3/2 for Approximating TSP in the Half-Integral Case
| Speaker: | Logan Grout |
| Affiliation: | University of Waterloo |
| Room: | MC 5417 |
Abstract:
In 2013, Schalekamp, Williamson, and van Zuylen conjectured that the integrality gap for the Subtour Polytope was attained on its half-integral vertices.
Title: Covers of Complete Bipartite Graphs
| Speaker: | Chris Godsil |
| Affiliation: | University of Waterloo |
| Room: | MC 5417 |
Abstract:
I will discuss antipodal distance-regular covers of complete bipartite graphs $K_{n,n}$. The index of such a cover is at most $n$.