English

Polynomial Invariants of q-Matroids and Rank-Metric Codes

Combinatorics 2025-09-29 v1 Information Theory math.IT

Abstract

It is shown that the Whitney function of a representable q-matroid and the collection of all higher weight enumerators of any representing rank-metric code determine each other via a monomial substitution. Moreover, the q-matroid itself and the collection of all higher support enumerators of the code determine each other. Next, it is proven that the Whitney function of a q-matroid and the Whitney function of its projectivization determine each other via a monomial substitution. Finally, q-matroids with isomorphic projectivizations are studied. It is shown that the projectivizations are isomorphic iff the q-matroids admit a dimension-preserving lattice isomorphism between their lattices of flats. Such q-matroids are called weakly isomorphic.

Keywords

Cite

@article{arxiv.2509.21618,
  title  = {Polynomial Invariants of q-Matroids and Rank-Metric Codes},
  author = {Heide Gluesing-Luerssen and Benjamin Jany},
  journal= {arXiv preprint arXiv:2509.21618},
  year   = {2025}
}