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In this article, we investigate the multi-parametric matroid problem. The weights of the elements of the matroid's ground set depend linearly on an arbitrary but fixed number of parameters, each of which is taken from a real interval. The…

Combinatorics · Mathematics 2025-03-13 Nils Hausbrandt , Stefan Ruzika

The classical volume polynomial in algebraic geometry measures the degrees of ample (and nef) divisors on a smooth projective variety. We introduce an analogous volume polynomial for matroids, and give a complete combinatorial formula. For…

Combinatorics · Mathematics 2019-08-20 Christopher Eur

We study a particular graded ring structure on the set of all loopfree matroids on a fixed labeled ground set, which occurs naturally in tropical geometry. The product is given by matroid intersection and the additive structure is defined…

Combinatorics · Mathematics 2016-09-05 Simon Hampe

Dowling and Rhodes defined different lattices on the set of triples (Subset, Partition, Cross Section) over a fixed finite group G. Although the Rhodes lattice is not a geometric lattice, it defines a matroid in the sense of the theory of…

Combinatorics · Mathematics 2017-10-17 Stuart W. Margolis , John Rhodes , Pedro V. Silva

This thesis is basically devoted to matroids -- fundamental structure of combinatorial optimization -- though some of our results concern simplicial complexes, or Euclidean spaces. We study old and new problems for these structures, with…

Combinatorics · Mathematics 2017-10-03 Michał Lasoń

Abstract polytopes are combinatorial structures with distinctive geometric, algebraic, or topological characteristics, that generalize (the face lattice of) traditional polyhedra, polytopes or tessellations. Most research has focused on…

Combinatorics · Mathematics 2026-04-02 Isabel Hubard , Egon Schulte

We study conic divisorial ideals from the viewpoint of matroid theory and apply the resulting framework to toric rings arising from signed posets. For a toric ring, we describe the polytope representing divisor classes corresponding to…

Commutative Algebra · Mathematics 2026-05-05 Koji Matsushita

We give explicit recursive constructions for the polytope of all matroids $\Omega_{r,n}$ in ranks 2 and 3 for all ground set sizes. This polytope was introduced in recent work by Ferroni and Fink as a tool for checking positivity…

Combinatorics · Mathematics 2026-05-13 Narayan Collins , Victoria Schleis

Hypergraphics matroids were studied first by Lorea and later by Frank et al. They can be seen as generalizations of graphic matroids. Here we show that several algorithms developed for the graphic case can be extended to hypergraphic…

Combinatorics · Mathematics 2021-11-11 Mourad Baiou , Francisco Barahona

It is well known that in q-matroids, axioms for independent spaces, bases, and spanning spaces differ from the classical case of matroids, since the straightforward q-analogue of the classical axioms does not give a q-matroid. For this…

Combinatorics · Mathematics 2024-04-24 Michela Ceria , Relinde Jurrius

We define and study q-delta-matroids, and q-g-matroids. These objects are analogues, for finite-dimensional vector spaces over finite fields, of delta-matroids and g-matroids arising from finite sets. We compare axiomatic descriptions with…

Combinatorics · Mathematics 2025-05-08 Michela Ceria , Trygve Johnsen , Relinde Jurrius

We study the complexity of testing if two given matroids are isomorphic. The problem is easily seen to be in $\Sigma_2^p$. In the case of linear matroids, which are represented over polynomially growing fields, we note that the problem is…

Computational Complexity · Computer Science 2008-11-25 Raghavendra Rao B. V. , Jayalal M. N. Sarma

This paper compares skew-linear and multilinear matroid representations. These are matroids that are representable over division rings and (roughly speaking) invertible matrices, respectively. The main tool is the von Staudt construction,…

Combinatorics · Mathematics 2025-05-21 Lukas Kühne , Rudi Pendavingh , Geva Yashfe

Border bases arise as a canonical generalization of Gr\"obner bases. We provide a polyhedral characterization of all order ideals (and hence border bases) that are supported by a zero-dimensional ideal: order ideals that support a border…

Commutative Algebra · Mathematics 2016-10-26 Gábor Braun , Sebastian Pokutta

Blasiak verified a conjecture of White for graphic matroids by showing that the toric ideal of a graphic matroid is generated by quadrics. In this paper, we extend this result to frame matroids satisfying a linearity condition. Such classes…

Combinatorics · Mathematics 2020-04-10 Sean McGuinness

A fundamental theorem of matroid theory establishes that a transversal matroid is representable over fields of any characteristic. It was proved in 1970 by Piff and Welsh: their proof is elegant and concise and, moveover, constructive.…

Combinatorics · Mathematics 2017-07-24 Carrie Rutherford , Robin Whitty

In this paper we provide an analytical procedure which leads to a system of $(n-2)^2$ polynomial equations whose solutions give the parameterisation of the complex $n\times n$ Hadamard matrices. It is shown that in general the Hadamard…

Quantum Physics · Physics 2016-09-08 Petre Dita

Is it possible to define cryptomorphic axiom systems for infinite oriented matroids by lifting some of the axiom systems for finite oriented matroids to the infinite setting while not losing duality in the process? We show that the answer…

Combinatorics · Mathematics 2026-03-18 Nathan Bowler , Winfried Hochstättler , Stefan Kaspar

We extend the definition of coarse flag Hilbert--Poincar\'e series to matroids; these series arise in the context of local Igusa zeta functions associated to hyperplane arrangements. We study these series in the case of oriented matroids by…

Combinatorics · Mathematics 2025-05-21 Lukas Kühne , Joshua Maglione

The Chow ring of a matroid (or more generally, atomic latice) is an invariant whose importance was demonstrated by Adiprasito, Huh and Katz, who used it to resolve the long-standing Heron-Rota-Welsh conjecture. Here, we make a detailed…

Combinatorics · Mathematics 2023-11-16 Thomas Hameister , Sujit Rao , Connor Simpson