Contraction and restriction of positroids in terms of decorated permutations

Abstract

A positroid is a matroid defined by Postnikov to study the cells in the non-negative part of the Grassmannian. They are in bijection with decorated permutations. We show a way to explain contraction and restriction of positroids in terms of decorated permutations.

arXiv commentMajor overhaul for readability, submitted to Annals of Combinatorics

References in corpus (1)

• Total positivity, Grassmannians, and networks