Events for 04/05/2024 from all calendars

Mathematical Physics and Harmonic Analysis Seminar

Time: 1:50PM - 2:50PM

Location: BLOC 302

Speaker: Theo McKenzie, Stanford

Title: Quantum Ergodicity for Periodic Graphs

Abstract: Quantum ergodicity (QE) is a notion of eigenfunction delocalization, that large Laplacian eigenfunction entries are “well spread” throughout a manifold or graph. Such a property is true of chaotic manifolds and graphs, such as random regular graphs and Riemannian manifolds with ergodic geodesic flow. Focusing on graphs, outside of very specific examples, QE was previously only known to hold for families of graphs with a tree local limit. In this talk we show how QE is in fact satisfied for many families of operators on periodic graphs, including Schrodinger operators with periodic potential on the discrete torus and on the honeycomb lattice.

In order to do this, we use new ideas coming from analyzing Bloch varieties and some methods coming from proofs in the continuous setting. Based on joint work with Mostafa Sabri.

Noncommutative Geometry Seminar

Time: 3:00PM - 4:00PM

Location: BLOC 628

Speaker: Ningfeng Wang, Tsinghua University

Title: 3d connections in alterfold TQFT and embedding theorems

Abstract: We give a 3d topological representation of flat connections within 3-alterfold TQFT. We give a quick proof of the embedding theorem saying that a multi-fusion category as a planar algebra can be canonically embedded into its graph planar algebra. Moreover, the image is the flat part of the connection. It generalizes the corresponding results for subfactors to any field. Furthermore, we developed an embedding theorem for ground states in the configuration spaces of the Levin-Wen model on a surface with/without boundary. This is joint work with Zhengwei Liu.

Algebra and Combinatorics Seminar

Time: 3:00PM - 3:50PM

Location: BLOC 302

Speaker: Chun-Hung Liu, TAMU

Title: Asymptotically optimal proper conflict-free coloring of bounded maximum degree graphs

Abstract: Every graph of maximum degree d has a coloring with d+1 colors such that no two adjacent vertices receive the same color. Caro, Petrusevski, Skrekovski conjectured that if d >2, then one can always choose such a proper (d+1)-coloring such that for every non-isolated vertex, some color appears on its neighborhood exactly once. We prove that this conjecture holds asymptotically: every graph of maximum degree d has a proper coloring with (1+o(1))d colors such that for every non-isolated vertex, some color appears on its neighborhood exactly once. Joint work with Bruce Reed.

Maxson Lecture Series

Time: 4:00PM - 5:00PM

Location: BLOC 117

Speaker: David Eisenbud, University of California, Berkeley

Title: Infinite Resolutions II: The biggest resolutions.

Geometry Seminar

Time: 6:00PM - 7:00PM

Location: TBA

Title: Texas Algebraic Geometry Symposium (TAGS)

Abstract: see https://franksottile.github.io/conferences/TAGS24/index.html