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Related papers: Representability of Flag Matroids

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A matroid is $\text{GF}(q)$-regular if it is representable over all proper superfields of the field $\text{GF}(q)$. We show that, for highly connected matroids having a large projective geometry over $\text{GF}(q)$ as a minor, the property…

Combinatorics · Mathematics 2014-01-29 Peter Nelson , Stefan H. M. van Zwam

Flag matroids are a rich family of Coxeter matroids that can be characterized using pairs of matroids that form a quotient. We consider a class of matroids called positroids, introduced by Postnikov, and utilize their combinatorial…

Combinatorics · Mathematics 2019-12-17 Carolina Benedetti , Anastasia Chavez , Daniel Tamayo

Every bi-uniform matroid is representable over all sufficiently large fields. But it is not known exactly over which finite fields they are representable, and the existence of efficient methods to find a representation for every given…

Combinatorics · Mathematics 2014-07-29 Simeon Ball , Carles Padró , Zsuzsa Weiner , Chaoping Xing

In this paper, we give a new axioms system based on nonseparable flats with their ranks to define a matroid. We deduce a polynomial time algorithm for deciding if a given matroid (respectively, arbitrary structure) is an uniform matroid.…

Combinatorics · Mathematics 2024-02-15 Brahim Chaourar

We introduce combinatorial objects named matricubes that provide a generalization of the theory of matroids. As matroids provide a combinatorial axiomatization of hyperplane arrangements, matricubes provide a combinatorial axiomatization of…

Combinatorics · Mathematics 2024-04-03 Omid Amini , Lucas Gierczak

Flag matroids are combinatorial abstractions of flags of linear subspaces, just as matroids are of linear subspaces. We introduce the flag Dressian as a tropical analogue of the partial flag variety, and prove a correspondence between: (a)…

Combinatorics · Mathematics 2021-03-08 Madeline Brandt , Christopher Eur , Leon Zhang

We extend the notion of matroid representations by matrices over fields and consider new representations of matroids by matrices over finite semirings, more precisely over the boolean and the superboolean semirings. This idea of…

Combinatorics · Mathematics 2011-03-03 Zur Izhakian , John Rhodes

There exist several theorems which state that when a matroid is representable over distinct fields F_1,...,F_k, it is also representable over other fields. We prove a theorem, the Lift Theorem, that implies many of these results. First,…

Combinatorics · Mathematics 2011-01-14 R. A. Pendavingh , S. H. M. van Zwam

We generalize Baker-Bowler's theory of matroids over tracts to orthogonal matroids, define orthogonal matroids with coefficients in tracts in terms of Wick functions, orthogonal signatures, circuit sets, and orthogonal vector sets, and…

Combinatorics · Mathematics 2025-08-13 Tong Jin , Donggyu Kim

We present a new type of equivalence for representable matroids that uses the automorphisms of the underlying matroid. Two $r\times n$ matrices $A$ and $A'$ representing the same matroid $M$ over a field $F$ are {\it geometrically…

Combinatorics · Mathematics 2015-09-16 S. R. Kingan

In this paper we give a necessary and sufficient criterion for representability of a matroid over an algebraic closed field. This leads to an algorithm, based on an extension of Groebner Bases, in order to decide if a given matroid is…

Combinatorics · Mathematics 2007-05-23 Massimiliano Lunelli , Antonio Laface

This paper is a direct generalization of Baker-Bowler theory to flag matroids, including its moduli interpretation as developed by Baker and the second author for matroids. More explicitly, we extend the notion of flag matroids to flag…

Combinatorics · Mathematics 2024-01-17 Manoel Jarra , Oliver Lorscheid

A flag matroid can be viewed as a chain of matroids linked by quotients. Flag matroids, of which relatively few interesting families have previously been known, are a particular class of Coxeter matroids. In this paper we give a family of…

Combinatorics · Mathematics 2007-05-23 Anna de Mier

We study a matrix-based notion of matroid representation over local commutative rings obtained by replacing linear independence with modular independence. This construction always defines an independence system, though not necessarily a…

Combinatorics · Mathematics 2026-03-11 Koji Imamura , Keisuke Shiromoto

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

It has recently been shown that infinite matroids can be axiomatized in a way that is very similar to finite matroids and permits duality. This was previously thought impossible, since finitary infinite matroids must have non-finitary…

Combinatorics · Mathematics 2012-07-12 Henning Bruhn , Reinhard Diestel

Thin sums matroids were introduced to extend the notion of representability to non-finitary matroids. We give a new criterion for testing when the thin sums construction gives a matroid. We show that thin sums matroids over thin families…

Combinatorics · Mathematics 2012-04-30 Hadi Afzali , Nathan Bowler

In this thesis, we study nearly finitary matroids by introducing new definitions and prove various properties of nearly finitary matroids. In 2010, an axiom system for infinite matroids was proposed by Bruhn et al. We use this axiom system…

Combinatorics · Mathematics 2019-06-13 Patrick Tam

We introduce the concept of orientation for Lagrangian matroids represented in the flag variety of maximal isotropic subspaces of dimension N in the real vector space of dimension 2N+1. The paper continues the study started in…

Combinatorics · Mathematics 2007-05-23 Richard F. Booth , Alexandre V. Borovik , Neil White

This paper introduces combinatorial representations, which generalise the notion of linear representations of matroids. We show that any family of subsets of the same cardinality has a combinatorial representation via matrices. We then…

Combinatorics · Mathematics 2011-09-07 Peter J. Cameron , Maximilien Gadouleau , Søren Riis
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