This is an old revision of the document!
Table of Contents
Fall 2026 Meeting Schedule
All meetings take place on Wednesdays, 9:30 - 10:20 am in Burt Hall 204 unless otherwise noted.
| Date | Meeting Title | Speaker | University | Abstract | |||||
|---|---|---|---|---|---|---|---|---|---|
| August 26 | Organizational Meeting | ||||||||
| September 2 | Vertex-Minimal Subgraphs with K_n Minors | David Hathaway | Kansas State University | Abstract | |||||
| September 9 | |||||||||
| Jiyoung Choi | Kansas State University | Generalized Nash equilibrium problems describe strategic interactions in which each player’s feasible choices may depend on the other players’ decisions. In this talk, I will present an algorithm for games with polynomial objectives and constraints that are linear in each player’s own strategy. The key idea is to use Carathéodory’s theorem and partial Lagrange multiplier expressions to decompose the Karush–Kuhn–Tucker (KKT) set into simpler subsets, leading to a collection of polynomial optimization problems. I will explain how the algorithm identifies equilibrium candidates and verifies them in the nonconvex setting, and discuss conditions under which it can find all equilibria or detect their nonexistence. Time permitting, I will discuss global optimization methods for solving the polynomial optimization problems arising in this approach. | |||||||
| September 16 | Notes on the Transfer-Impedance matrix. | Pietro Poggi-Corradini | Kansas State University | This summer I started collecting some notes on this fascinating topic. I will start from the beginning and lay down the basic definitions, which means that I won't get to the Burton-Pemantle Theorem in one hour. However, that is the goal and hopefully we will get there in subsequent talks. After that we can start looking at the many applications of this matrix.| | September 23 | TBA | Pietro Poggi-Corradini | Kansas State University | |
| September 30 | Duality for the Dirichlet and Thomson problems on networks | Andrew Jensen | Kansas State University | ||||||
| October 7 | |||||||||
| October 14 | |||||||||
| October 21 | |||||||||
| October 28 | |||||||||
| November 4 | |||||||||
| November 11 | |||||||||
| November 18 | |||||||||
| November 25 | No Meeting (fall break) | ||||||||
| December 2 | |||||||||
| December 9 |
Abstracts
September 2
“Vertex-Minimal Subgraphs with K_n Minors”, David Hathaway
Let h(G) be the Hadwiger number of G, the largest n such that G has a K_n minor, and define h_n(G) = min{|V(H)| : H\subset G, h(H)=n}, defined for any n = 1, 2, …, h(G). We seek to study the structure of any given graph through this sequence of orders and its long-term behavior. As a result, the primary focus will be on infinite graphs, in particular those with infinite Hadwiger number. We shall investigate lower bounds originating from basic structural details or from partial knowledge of early elements in the sequence. Along the way, we'll work many examples of interesting finite and infinite graphs.