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Related papers: Flag enumerations of matroid base polytopes

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We introduce flag positroid pipe dreams (FPPs), whose role in the study of complete flag positroids is analogous to the role of Le-diagrams in the study of positroids. We develop the combinatorics of these diagrams and highlight some of…

Combinatorics · Mathematics 2026-05-26 Williem Rizer , Martha Yip

Let p be a singular point of a variety. Consider a resolution where the preimage of p is a simple normal crossing divisor E. The combinatorial structure of E is described by a cell complex D(E), called the dual graph or dual complex of E.…

Algebraic Geometry · Mathematics 2012-03-14 János Kollár

The propagation of a surface plasmon-polariton along a stack of doped graphene sheets is considered. This auxiliary problem is used to discuss: (i) the scattering of such a mode at an interface between the stack and the vacuum; (ii) the…

Mesoscale and Nanoscale Physics · Physics 2016-06-29 Yu. V. Bludov , N. M. R. Peres , G. Smirnov , M. I. Vasilevskiy

A notion of branch-width, which generalizes the one known for graphs, can be defined for matroids. We first give a proof of the polynomial time model-checking of monadic second-order formulas on representable matroids of bounded…

Discrete Mathematics · Computer Science 2015-03-13 Yann Strozecki

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

Swartz proved that any matroid can be realized as the intersection lattice of an arrangement of codimension one homotopy spheres on a sphere. This was an unexpected extension from the oriented matroid case, but unfortunately the…

Combinatorics · Mathematics 2015-03-13 Alexander Engstrom

Bisztriczky defines a multiplex as a generalization of a simplex, and an ordinary polytope as a generalization of a cyclic polytope. This paper presents results concerning the combinatorics of multiplexes and ordinary polytopes. The flag…

Combinatorics · Mathematics 2007-05-23 Margaret M. Bayer , Aaron M. Bruening , Joshua Stewart

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

We study paving matroids, their realization spaces, and their closures, along with matroid varieties and circuit varieties. Within this context, we introduce three distinct methods for generating polynomials within the associated ideals of…

Algebraic Geometry · Mathematics 2026-03-24 Emiliano Liwski , Fatemeh Mohammadi

Symmetric edge polytopes are lattice polytopes associated with finite simple graphs that are of interest in both theory and applications. We investigate the facet structure of symmetric edge polytopes for various models of random graphs.…

Combinatorics · Mathematics 2024-02-14 Benjamin Braun , Kaitlin Bruegge , Matthew Kahle

The purpose of this note is to define tri-moment maps for certain manifolds that carry closed non-degenerate 4-forms and an $Sp(1)^n$-action. Examples include quaternionic vector spaces and flag manifolds. We show how this map can be used…

Differential Geometry · Mathematics 2009-11-07 Philip Foth

Magic labelings of graphs are studied in great detail by Stanley and Stewart. In this article, we construct and enumerate magic labelings of graphs using Hilbert bases of polyhedral cones and Ehrhart quasi-polynomials of polytopes. We…

Combinatorics · Mathematics 2007-05-23 Maya Mohsin Ahmed

This paper investigates the problem of listing faces of combinatorial polytopes, such as hypercubes, permutahedra, associahedra, and their generalizations. Firstly, we consider the face lattice, which is the inclusion order of all faces of…

Describing the combinatorial structure of the tropical complex $C$ of a tropical matroid polytope, we obtain a formula for the coarse types of the maximal cells of $C$. Due to the connection between tropical complexes and resolutions of…

Combinatorics · Mathematics 2010-12-16 Katja Kulas

We extend the splitting operation from binary matroids (Raghunathan et al., 1998) to $p$- matroids, where $p$-matroids refer to matroids representable over $GF(p).$ We also characterize circuits, bases, and independent sets of the resulting…

Combinatorics · Mathematics 2025-07-15 Prashant Malavadkar , Uday Jagadale , Sachin Gunjal

As part of the recent developments in infinite matroid theory, there have been a number of conjectures about how standard theorems of finite matroid theory might extend to the infinite setting. These include base packing, base covering, and…

Combinatorics · Mathematics 2012-03-06 Nathan Bowler , Johannes Carmesin

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

We study the combinatorial properties of a tropical hyperplane arrangement. We define tropical oriented matroids, and prove that they share many of the properties of ordinary oriented matroids. We show that a tropical oriented matroid…

Combinatorics · Mathematics 2007-06-25 Federico Ardila , Mike Develin

The index coding problem has been generalized recently to accommodate receivers which demand functions of messages and which possess functions of messages. The connections between index coding and matroid theory have been well studied in…

Information Theory · Computer Science 2017-05-02 Anoop Thomas , B. Sundar Rajan

The intersection data of a hyperplane arrangement is described by a geometric lattice, or equivalently a simple matroid. There is a rich interplay between this combinatorial structure and the topology of the arrangement complement. In this…

Combinatorics · Mathematics 2025-04-22 Christin Bibby