Universality for valuations of (poly)matroid polytope decompositionsAlgebra & Discrete Mathematics
|Speaker:||Alexander Fink, UC Berkeley|
|Start time:||Fri, Dec 4 2009, 4:10PM|
Many important matroid and polymatroid invariants are valuations of polytope decompositions. We construct explicit bases for the modules of matroids and polymatroids on a fixed ground set modulo relations given by decompositions, and their duals, the modules of valuations on (poly)matroid base polytopes. The basis elements for matroid polytopes are essentially the Schubert matroids. We also discuss some variants of this basic problem.
This work is joint with Harm Derksen.