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Related papers: White's Conjecture for Paving Matroids

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In the spirit of a theorem of Wood, we give necessary and sufficient conditions for a family of germs of analytic hypersurfaces in a smooth projective toric variety X to be interpolated by an algebraic hypersurface with a fixed class in the…

Complex Variables · Mathematics 2007-05-23 Martin Weimann

We explore a combinatorial theory of linear dependency in complex space, "complex matroids", with foundations analogous to those for oriented matroids. We give multiple equivalent axiomatizations of complex matroids, showing that this…

Combinatorics · Mathematics 2013-03-27 Laura Anderson , Emanuele Delucchi

We give a combinatorial formula for the Ehrhart coefficients of a certain class of weighted multi-hypersimplices. In a special case, where these polytopes coincide with the base polytope of the panhandle matroid $\textrm{Pan}_{k,n-2,n}$, we…

Combinatorics · Mathematics 2023-12-13 Daniel McGinnis

The Whitney module of a matroid is a natural analogue of the tensor algebra of the exterior algebra of a vector space that takes into account the dependencies of a matroid. In this paper we indicate the role that tableaux can play in…

Combinatorics · Mathematics 2010-06-17 Andrew Berget

B\'ar\'any, Kalai, and Meshulam recently obtained a topological Tverberg-type theorem for matroids, which guarantees multiple coincidences for continuous maps from a matroid complex to d-dimensional Euclidean space, if the matroid has…

Combinatorics · Mathematics 2017-05-11 Pavle V. M. Blagojević , Albert Haase , Günter M. Ziegler

The multiple exchange property for matroid bases states that for any bases $A$ and $B$ of a matroid and any subset $X\subseteq A\setminus B$, there exists a subset $Y\subseteq B\setminus A$ such that both $A-X+Y$ and $B+X-Y$ are bases. This…

Combinatorics · Mathematics 2026-05-05 Taihei Oki , Tamás Schwarcz

We provide a formula for the Ehrhart polynomial of the connected matroid of size $n$ and rank $k$ with the least number of bases, also known as a minimal matroid. We prove that their polytopes are Ehrhart positive and $h^*$-real-rooted (and…

Combinatorics · Mathematics 2021-06-17 Luis Ferroni

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

Multimatroids generalize matroids, delta-matroids, and isotropic systems, and transition polynomials of multimatroids subsume various polynomials for these latter combinatorial structures, such as the interlace polynomial and the…

Combinatorics · Mathematics 2017-08-18 Robert Brijder

We introduce the minor-closed, dual-closed class of multi-path matroids. We give a polynomial-time algorithm for computing the Tutte polynomial of a multi-path matroid, we describe their basis activities, and we prove some basic structural…

Combinatorics · Mathematics 2024-08-07 Joseph E. Bonin , Omer Gimenez

A well-known conjecture states that the Whitney numbers of the second kind of a geometric lattice (simple matroid) are logarithmically concave. We show this conjecture to be equivalent to proving an upper bound on the number of new copoints…

Combinatorics · Mathematics 2011-11-10 W. M. B. Dukes

The Mayhew--Newman--Welsh--Whittle conjecture predicts that asymptotically almost all matroids are sparse paving. We study the gap between paving and sparse paving matroids at the logarithmic scale. Let \(p_n\) be the number of paving…

Combinatorics · Mathematics 2026-05-13 Mohsen Aliabadi

We give two proofs that the $h$-vector of any paving matroid is a pure O-sequence, thus answering in the affirmative a conjecture made by R. Stanley, for this particular class of matroids. We also investigate the problem of obtaining good…

Combinatorics · Mathematics 2010-08-17 Criel Merino , Steven D. Noble , Marcelino Ramírez-Ibañez , Rafael Villarroel

Cyclic flats form a common structural invariant of both matroids and $q$-matroids, determining these objects through their weighted lattices of cyclic flats. In this paper we exploit this perspective to establish a correspondence between…

Combinatorics · Mathematics 2026-03-17 Andrew Fulcher

We present an algebraic framework which simultaneously generalizes the notion of linear subspaces, matroids, valuated matroids, and oriented matroids. We call the resulting objects matroids over hyperfields. In fact, there are (at least)…

Combinatorics · Mathematics 2017-04-21 Matthew Baker , Nathan Bowler

A new connection between two different necessary conditions for a polymatroid to be linearly representable is presented. Specifically, we prove that the existence of a tensor product with the uniform matroid of rank two on three elements…

Combinatorics · Mathematics 2025-02-20 Carles Padró

We introduce certain torus-equivariant classes on permutohedral varieties which we call "tautological classes of matroids" as a new geometric framework for studying matroids. Using this framework, we unify and extend many recent…

Combinatorics · Mathematics 2023-04-17 Andrew Berget , Christopher Eur , Hunter Spink , Dennis Tseng

We characterize 2-dimensional complexes associated canonically with basis graphs of matroids as simply connected triangle-square complexes satisfying some local conditions. This proves a version of a (disproved) conjecture by Stephen Maurer…

Combinatorics · Mathematics 2018-12-10 Jérémie Chalopin , Victor Chepoi , Damian Osajda

We begin with a review of Tutte's homotopy theory, which concerns the structure of certain graph associated to a matroid (together with some extra data). Concretely, Tutte's path theorem asserts that this graph is connected, and his…

Combinatorics · Mathematics 2026-01-21 Matthew Baker , Tong Jin , Oliver Lorscheid

There is a long list of open questions rooted in the same underlying problem: understanding the structure of bases or common bases of matroids. These conjectures suggest that matroids may possess much stronger structural properties than are…

Combinatorics · Mathematics 2024-11-05 Kristóf Bérczi , Áron Jánosik , Bence Mátravölgyi