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Related papers: Matroid polytopes, nested sets and Bergman fans

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In this paper, we classify singular real plane tropical curves by means of subdivisions of Newton polytopes. First, we introduce signed Bergman fans (generalizing positive Bergman fans from [AKW06]) that describe real tropicalizations of…

Algebraic Geometry · Mathematics 2018-02-07 Christian Jürgens

We study structural and topological properties of nested set complexes of matroids with arbitrary building sets, proving that these complexes are vertex decomposable and admit convex ear decompositions. These results unify and generalize…

Combinatorics · Mathematics 2026-01-19 Basile Coron , Luis Ferroni , Shiyue Li

Generalized permutohedra are deformations of regular permutohedra, and arise in many different fields of mathematics. One important characterization of generalized permutohedra is the Submodular Theorem, which is related to the deformation…

Combinatorics · Mathematics 2020-05-21 Federico Castillo , Fu Liu

We construct an intersection product on tropical cycles contained in the Bergman fan of a matroid. To do this we first establish a connection between the operations of deletion and restriction in matroid theory and tropical modifications as…

Algebraic Geometry · Mathematics 2011-10-05 Kristin M. Shaw

Given a matroid M on the ground set E, the Bergman fan B(M), or space of M-ultrametrics, is a polyhedral complex in R^E which arises in several different areas, such as tropical algebraic geometry, dynamical systems, and phylogenetics.…

Combinatorics · Mathematics 2007-05-23 Federico Ardila

We study moduli spaces of rational graphically stable tropical curves and a refinement given by radial alignment. Given a complete multipartite graph $\Gamma$, the moduli space of radially aligned $\Gamma$-stable tropical curves can be…

Combinatorics · Mathematics 2019-10-03 Andy Fry

We study a notion of tropical linear series on metric graphs that combines two essential properties of tropicalizations of linear series on algebraic curves: the Baker-Norine rank and the independence rank. Our main results relate the local…

Algebraic Geometry · Mathematics 2025-09-05 Chih-Wei Chang , Matthew Dupraz , Hernan Iriarte , David Jensen , Dagan Karp , Sam Payne , Jidong Wang

Inspired by Bruggesser-Mani's line shellings of polytopes, we introduce line shellings for the lattice of flats of a matroid: given a normal complex for a Bergman fan of a matroid induced by a building set, we show that the lexicographic…

Combinatorics · Mathematics 2026-01-09 Spencer Backman , Galen Dorpalen-Barry , Anastasia Nathanson , Ethan Partida , Noah Prime

The augmented Bergman complex of a matroid is a simplicial complex introduced recently in work of Braden, Huh, Matherne, Proudfoot and Wang. It may be viewed as a hybrid of two well-studied pure shellable simplicial complexes associated to…

We introduce the Bergman fan of a polymatroid and prove that the Chow ring of the Bergman fan is isomorphic to the Chow ring of the polymatroid. Using the Bergman fan, we establish the K\"ahler package for the Chow ring of the polymatroid,…

Combinatorics · Mathematics 2024-01-19 Colin Crowley , June Huh , Matt Larson , Connor Simpson , Botong Wang

We establish a correspondence between simplicial fans, not necessarily rational, and certain foliated compact complex manifolds called LVMB-manifolds. In the rational case, Meersseman and Verjovsky have shown that the leaf space is the…

Complex Variables · Mathematics 2015-03-31 Fiammetta Battaglia , Dan Zaffran

Given two tropical polynomials $f, g$ on $\mathbb{R}^n$, we provide a characterization for the existence of a factorization $f= h \odot g$ and the construction of $h$. As a ramification of this result we obtain a parallel result for the…

Combinatorics · Mathematics 2019-08-02 Robert Alexander Crowell

We study the fan structure of Dressians $\Dr(d,n)$ and local Dressians $\Dr(\cM)$ for a given matroid $\cM$. In particular we show that the fan structure on $\Dr(\cM)$ given by the three term Pl\"ucker relations coincides with the structure…

Combinatorics · Mathematics 2018-09-25 Jorge Alberto Olarte , Marta Panizzut , Benjamin Schröter

An affine tropical fan is called regular if it supports a reduced 0-dimensional complete intersection. For some cases the classification of regular fans is already complete. It was proved by Fink that tropical varieties of degree 1 are…

Combinatorics · Mathematics 2025-12-19 Linxuan Li

The theory of matroids or combinatorial geometries originated in linear algebra and graph theory, and has deep connections with many other areas, including field theory, matching theory, submodular optimization, Lie combinatorics, and total…

Combinatorics · Mathematics 2021-11-18 Federico Ardila

We give several characterizations of stable intersections of tropical cycles and establish their fundamental properties. We prove that the stable intersection of two tropical varieties is the tropicalization of the intersection of the…

Algebraic Geometry · Mathematics 2016-08-12 Anders Jensen , Josephine Yu

Nested set complexes appear as the combinatorial core of De Concini-Procesi arrangement models. We show that nested set complexes are homotopy equivalent to the order complexes of the underlying meet-semilattices without their minimal…

Combinatorics · Mathematics 2007-05-23 Eva Maria Feichtner , Irene Mueller

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 study the augmented Bergman complex of a closure operator on a finite set, which interpolates between the order complex of proper flats and the independence complex of the operator. In 2020, Braden, Huh, Matherne, Proudfoot, and Wang…

Combinatorics · Mathematics 2022-04-13 R. Amzi Jeffs

Normal complexes are orthogonal truncations of polyhedral fans. In this paper, we develop the study of mixed volumes for normal complexes. Our main result is a sufficiency condition that ensures when the mixed volumes of normal complexes…

Combinatorics · Mathematics 2023-01-16 Lauren Nowak , Patrick O'Melveny , Dustin Ross