English

A cyclic flat embedding theorem for transversal $q$-matroids

Combinatorics 2026-03-17 v1

Abstract

Cyclic flats form a common structural invariant of both matroids and qq-matroids, determining these objects through their weighted lattices of cyclic flats. In this paper we exploit this perspective to establish a correspondence between matroids and a subclass of qq-matroids that we call coordinate qq-matroids. Our main result is a cyclic flat embedding theorem showing that the cyclic flat structure of a transversal matroid is preserved under this correspondence. This provides a mechanism for transferring structural properties from matroid theory to the qq-matroid setting. As an application, we show that nested qq-matroids are transversal and therefore representable. Finally, we illustrate the usefulness of this perspective by analysing transversal qq-matroids under binary operations. We prove that the class of transversal qq-matroids is closed under the free product and propose a natural presentation for the direct sum motivated by the corresponding construction for matroids.

Keywords

Cite

@article{arxiv.2603.13550,
  title  = {A cyclic flat embedding theorem for transversal $q$-matroids},
  author = {Andrew Fulcher},
  journal= {arXiv preprint arXiv:2603.13550},
  year   = {2026}
}
R2 v1 2026-07-01T11:19:24.308Z