Excluding a line from complex-representable matroids

Series
Algebra Seminar
Time
Monday, February 13, 2023 - 10:20am for 1.5 hours (actually 80 minutes)
Location
Skiles 005
Speaker
Zach Walsh – Georgia Institute of Technology – zwalsh6@gatech.eduhttps://zachwalsh.math.gatech.edu/index.html
Organizer
Abeer Al Ahmadieh

The extremal function of a class of matroids maps each positive integer n to the maximum number of elements of a simple matroid in the class with rank at most n. We will present a result concerning the role of finite groups in minor-closed classes of matroids, and then use it to determine the extremal function for several natural classes of representable matroids. We will assume no knowledge of matroid theory. This is joint work with Jim Geelen and Peter Nelson.