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Related papers: Algebraic Geometry of Cactus, Pascal, and Pappus M…

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A $q$-matroid is the analogue of a matroid which arises by replacing the finite ground set of a matroid with a finite-dimensional vector space over a finite field. These $q$-matroids are motivated by coding theory as the representable…

Combinatorics · Mathematics 2025-11-27 Sebastian Degen , Lukas Kühne

Answering a question posed by Adam Epstein, we show that the collection of conjugacy classes of polynomials admitting a parabolic fixed point and at most one infinite critical orbit is a set of bounded height in the relevant moduli space.…

Number Theory · Mathematics 2017-06-19 Patrick Ingram

We consider three matroids defined by Kalai in 1985: the symmetric completion matroid $\mathcal{S}_d$ on the edge set of a looped complete graph; the hyperconnectivity matroid $\mathcal{H}_d$ on the edge set of a complete graph; and the…

Combinatorics · Mathematics 2026-03-17 Dániel Garamvölgyi , Bill Jackson , Tibor Jordán , Soma Villányi

Describing minimal generating set of a toric ideal is a well-studied and difficult problem. In 1980 White conjectured that the toric ideal associated to a matroid is equal to the ideal generated by quadratic binomials corresponding to…

Combinatorics · Mathematics 2014-04-01 Michał Lasoń , Mateusz Michałek

This is a revised version of our original paper (arXiv:1808.00489v2) incorporating the corrections published in a corrigendum (arXiv:1808.00489v3). Our main theorem as originally stated was missing the required assumption that matroids…

Combinatorics · Mathematics 2025-05-28 Nathan Bowler , Daryl Funk , Daniel Slilaty

To each prime ideal in a polynomial ring over a field we associate an algebraic matroid and show that it is preserved under tropicalization. This gives a necessary condition for a tropical variety to be set-theoretically realizable from a…

Combinatorics · Mathematics 2016-08-12 Josephine Yu

We give axiomatic foundations for non-finitary infinite matroids with duality, in terms of independent sets, bases, circuits, closure and rank. This completes the solution to a problem of Rado of 1966.

Combinatorics · Mathematics 2013-02-26 Henning Bruhn , Reinhard Diestel , Matthias Kriesell , Rudi Pendavingh , Paul Wollan

Many combinatorial properties of a point set in the plane are determined by the set of possible partitions of the point set by a line. Their essential combinatorial properties are well captured by the axioms of oriented matroids. In fact,…

Combinatorics · Mathematics 2021-11-08 Hiroyuki Miyata

We introduce a new model for the realization space of a matroid, which is obtained from a variety defined by a saturated determinantal ideal, called the slack ideal, coming from the vertex-hyperplane incidence matrix of the matroid. This is…

Combinatorics · Mathematics 2018-04-17 Madeline Brandt , Amy Wiebe

We consider the problem of finding a basis of a matroid with weight exactly equal to a given target. Here weights can be discrete values from $\{-\Delta,\ldots,\Delta\}$ or more generally $m$-dimensional vectors of such discrete values. We…

Data Structures and Algorithms · Computer Science 2024-08-27 Friedrich Eisenbrand , Lars Rohwedder , Karol Węgrzycki

For a lattice polytope $P$, the rank of $P$ is defined by $F-(\dim P+1)$, where $F$ is the number of facets of $P$. In this paper, we study matroid polytopes with small rank. More precisely, we characterize matroid independence polytopes…

Combinatorics · Mathematics 2025-03-31 Masato Konoike , Koji Matsushita

A matroid is supersolvable if it has a maximal chain of flats each of which is modular. A matroid is saturated if every round flat is modular. In this article we present supersolvable saturated matroids as analogues to chordal graphs, and…

Combinatorics · Mathematics 2023-01-12 Dillon Mayhew , Andrew Probert

Cactus groups and their pure subgroups appear in various fields of mathematics and are currently attracting attention from diverse mathematical communities. They share similarities with both right-angled Coxeter groups and braid groups. In…

Group Theory · Mathematics 2022-12-08 Anthony Genevois

The investigation of width parameters in both graph and algebraic contexts has attracted considerable interest. Among these parameters, the linear branch width has emerged as a crucial measure. In this concise paper, we explore the concept…

Combinatorics · Mathematics 2026-03-03 Takaaki Fujita

We exhibit an explicit formula for the cardinality of solutions to a class of quadratic matrix equations over finite fields. We prove that the orbits of these solutions under the natural conjugation action of the general linear groups can…

Rings and Algebras · Mathematics 2024-03-01 Yin Chen , Xinxin Zhang

In this paper we investigate a family of matroids introduced by Ardila and Billey to study one-dimensional intersections of complete flag arrangements of $\mathbb{C}^n$. The set of lattice points $P_n$ inside the equilateral triangle $S_n$…

Combinatorics · Mathematics 2018-11-20 Felix Gotti , Harold Polo

This paper develops matroidal analogues of classical results on matchings in abelian groups. By embedding matroid ground sets in an abelian group, we introduce base matchings between matroid bases, recover the group-theoretic setting in the…

Combinatorics · Mathematics 2026-04-21 Mohsen Aliabadi , Elliot Krop

Given an integral $d \times n$ matrix $A$, the well-studied affine semigroup $\mbox{ Sg} (A)=\{ b : Ax=b, \ x \in {\mathbb Z}^n, x \geq 0\}$ can be stratified by the number of lattice points inside the parametric polyhedra $P_A(b)=\{x:…

Combinatorics · Mathematics 2015-07-27 Iskander Aliev , Jesus A. De Loera , Quentin Louveaux

This thesis presents new applications of Gale duality to the study of polytopes, point configurations and oriented matroids with extremal combinatorial properties. The first part of the thesis explores construction techniques for neighborly…

Combinatorics · Mathematics 2013-04-29 Arnau Padrol

We investigate the asymptotic behavior of entropy polymatroids associated with algebraic matroids over finite fields. Given an algebraic matroid ${\sf M}:=(\mathcal{E},r)$ and the irreducible variety $V$ associated with ${\sf M}$, we…

Combinatorics · Mathematics 2025-09-22 Guillermo Matera