Graphs and Matroids - Matthew Kroeker

Tuesday, October 8, 2024 2:00 pm - 3:00 pm EDT (GMT -04:00)

Title: Unavoidable flats in matroids representable over a finite field

Speaker: Matthew Kroeker
Affiliation: University of Waterloo
Location: MC 5417

Abstract: For a positive integer k and finite field F, we prove that every simple F-representable matroid with sufficiently high rank has a rank-k flat which either is independent, or is a projective or affine geometry over a subfield of F.  As a corollary, we obtain the following Ramsey theorem: given an F-representable matroid of sufficiently high rank and any 2-colouring of its points,  there is a monochromatic rank-k flat.  This is joint work with Jim Geelen and Peter Nelson.