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Related papers: Presentations of Transversal Valuated Matroids

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A transversal matroid $M$ of rank $r$ on $[n]$ can be associated to a family of binary matrices corresponding to different presentations of $M$. We describe those matrices which arise from unique maximal presentations of size $r$- giving a…

Combinatorics · Mathematics 2019-09-11 Austin Alderete

Following up on our previous work, we study single-element extensions of transversal valuated matroids. We show that tropical presentations of valuated matroids with a minimal set of finite entries enjoy counterparts of the properties…

Combinatorics · Mathematics 2025-03-12 Alex Fink , Jorge Alberto Olarte

A tract $F$ is an algebraic structure where multiplication is defined but addition is only partially defined. They were introduced by Baker and Bowler as a unified framework to study generalisations of matroids, including oriented and…

Combinatorics · Mathematics 2024-06-06 Ben Smith

A transversal matroid whose dual is also transversal is called bi-transversal. Let $G$ be an undirected graph with vertex set $V$. In this paper, for every subset $W$ of $V$, we associate a bi-transversal matroid to the pair $(G,W)$. We…

Combinatorics · Mathematics 2024-03-01 Mahdi Ebrahimi

In this paper we address two of the major foundational questions in the theory of matroids over rings. First, we provide a cryptomorphic axiomatisation, by introducing an analogue of the base polytope for matroids. Second, we describe a…

Combinatorics · Mathematics 2017-08-02 Alex Fink , Luca Moci

We define an intersection product of tropical cycles on matroid varieties (via cutting out the diagonal) and show that it is well-behaved. In particular, this enables us to intersect cycles on moduli spaces of tropical rational marked…

Algebraic Geometry · Mathematics 2015-08-25 Georges Francois , Johannes Rau

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

A result of Mason, as refined by Ingleton, characterizes transversal matroids as the matroids that satisfy a set of inequalities that relate the ranks of intersections and unions of nonempty sets of cyclic flats. We prove counterparts, for…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Joseph P. S. Kung , Anna de Mier

Speyer recognized that matroids encode the same data as a special class of tropical linear spaces and Shaw interpreted tropically certain basic matroid constructions; additionally, Frenk developed the perspective of tropical linear spaces…

Algebraic Geometry · Mathematics 2023-03-03 Colin Crowley , Noah Giansiracusa , Joshua Mundinger

The spinor variety is cut out by the quadratic Wick relations among the principal Pfaffians of an n x n skew-symmetric matrix. Its points correspond to n-dimensional isotropic subspaces of a 2n-dimensional vector space. In this paper we…

Combinatorics · Mathematics 2013-03-07 Felipe Rincón

In classical geometry, a linear space is a space that is closed under linear combinations. In tropical geometry, it has long been a consensus that tropical varieties defined by valuated matroids are the tropical analogue of linear spaces.…

Algebraic Geometry · Mathematics 2015-05-11 Simon Hampe

We give a complete description of Green's D relation for the multiplicative semigroup of all n-by-n tropical matrices. Our main tool is a new variant on the duality between the row and column space of a tropical matrix (studied by Cohen,…

Rings and Algebras · Mathematics 2014-02-26 Christopher Hollings , Mark Kambites

We use the geometry of the stellahedral toric variety to study matroids. We identify the valuative group of matroids with the cohomology ring of the stellahedral toric variety, and show that valuative, homological, and numerical equivalence…

Algebraic Geometry · Mathematics 2023-09-08 Christopher Eur , June Huh , Matt Larson

It is known that the duals of transversal matroids are precisely the strict gammoids. The purpose of this short note is to show how the Lindstrom-Gessel-Viennot lemma gives a simple proof of this result.

Combinatorics · Mathematics 2007-05-23 Federico Ardila

In this paper, we study positroids and its overlap with two classes of matroids: transversal and paving matroids. We exhibit a new class of fundamental transversal matroids and classify the Le-diagram for rank two transversal positroids. We…

Combinatorics · Mathematics 2024-07-29 John Machacek , George D. Nasr

We provide a full classification of all families of matroids that are closed under duality and minors, and for which the Tutte polynomial is a universal valuative invariant. There are four inclusion-wise maximal families, two of which are…

Combinatorics · Mathematics 2025-02-10 Luis Ferroni , Benjamin Schröter

We present an algebraic framework which simultaneously generalizes the notion of linear subspaces, matroids, valuated matroids, oriented matroids, and regular matroids. To do this, we first introduce algebraic objects called tracts which…

Combinatorics · Mathematics 2018-12-13 Matthew Baker , Nathan Bowler

The goal of this paper is to introduce a construction of a vector bundle on a tropical variety. When the base is a tropical toric variety these tropicalize toric vector bundles, and are described by the data of a valuated matroid and some…

Algebraic Geometry · Mathematics 2024-05-07 Bivas Khan , Diane Maclagan

We introduce an idempotent analogue of the exterior algebra for which the theory of tropical linear spaces (and valuated matroids) can be seen in close analogy with the classical Grassmann algebra formalism for linear spaces. The top wedge…

Algebraic Geometry · Mathematics 2017-09-15 Jeffrey Giansiracusa , Noah Giansiracusa

Tropical oriented matroids were defined by Ardila and Develin in 2007. They are a tropical analogue of classical oriented matroids in the sense that they encode the properties of the types of points in an arrangement of tropical hyperplanes…

Combinatorics · Mathematics 2012-12-11 Silke Horn
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