An independent set axiomatization for symplectic matroids

Abstract

One of the simplest axiomatizations of a matroid is in terms of independent sets. Curiously, no such independent set axiomatization is known for Gelfand and Serganova's WP-matroids (which are ``Coxeter group analogues'' of matroids). Here we state and prove such an axiomatization in the special case of symplectic matroids. No prior knowledge of WP-matroids is assumed; we believe the paper should be accessible and interesting to anyone with some interest in matroids.