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Related papers: A Grassmann algebra for matroids

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We define a formal framework for the study of algebras of type Max-plus, Min-Plus, tropical algebras, and more generally algebras over a commutative idempotent semi-field. This work is motivated by the increasingly diversified use of these…

Commutative Algebra · Mathematics 2008-07-22 Dominique Castella

This article is a survey of matroid theory aimed at algebraic geometers. Matroids are combinatorial abstractions of linear subspaces and hyperplane arrangements. Not all matroids come from linear subspaces; those that do are said to be…

Algebraic Geometry · Mathematics 2014-09-12 Eric Katz

Phylogenetic trees provide a fundamental representation of evolutionary relationships, yet the combinatorial explosion of possible tree topologies renders inference computationally challenging. Classical approaches to characterizing tree…

Populations and Evolution · Quantitative Biology 2025-12-29 Samir Bhatt , John Sabol , Papri Dey , Matthew J. Penn , David Duchene , Ruriko Yoshida

The first problem we investigate is the following: given $k\in \mathbb{R}_{\ge 0}$ and a vector $v$ of Pl\"ucker coordinates of a point in the real Grassmannian, is the vector obtained by taking the $k$th power of each entry of $v$ again a…

Combinatorics · Mathematics 2019-10-03 Matthias Lenz

This paper introduces a new structure of commutative semiring, generalizing the tropical semiring, and having an arithmetic that modifies the standard tropical operations, i.e. summation and maximum. Although our framework is combinatorial,…

Algebraic Geometry · Mathematics 2010-08-02 Zur Izhakian

The tropical Stiefel map associates to a tropical matrix A its tropical Pluecker vector of maximal minors, and thus a tropical linear space L(A). We call the L(A)s obtained in this way Stiefel tropical linear spaces. We prove that they are…

Combinatorics · Mathematics 2015-06-02 Alex Fink , Felipe Rincón

In this paper we study general tropical linear spaces locally: For any basis B of the matroid underlying a tropical linear space L, we define the local tropical linear space L_B to be the subcomplex of L consisting of all vectors v that…

Combinatorics · Mathematics 2013-10-14 Felipe Rincón

In this paper, we present a lattice-theoretic characterization for valuated matroids, which is an extension of the well-known cryptomorphic equivalence between matroids and geometric lattices ($=$ atomistic semimodular lattices). We…

Combinatorics · Mathematics 2019-03-04 Hiroshi Hirai

The tropical variety of a $d$-dimensional prime ideal in a polynomial ring with complex coefficients is a pure $d$-dimensional polyhedral fan. This fan is shown to be connected in codimension one. We present algorithmic tools for computing…

Algebraic Geometry · Mathematics 2009-12-16 Tristram Bogart , Anders Jensen , David Speyer , Bernd Sturmfels , Rekha Thomas

A fully tensorial theoretical framework for hypercomplex-valued neural networks is presented. The proposed approach enables neural network architectures to operate on data defined over arbitrary finite-dimensional algebras. The central…

Machine Learning · Computer Science 2026-01-27 Agnieszka Niemczynowicz , Radosław Antoni Kycia

Let G(d,n) denote the Grassmannian of d-planes in C^n and let T be the torus (C^*)^n/diag(C^*) which acts on G(d,n). Let x be a point of G(d,n) and let \bar{Tx} be the closure of the T-orbit through x. Then the class of the structure sheaf…

Algebraic Geometry · Mathematics 2007-05-23 David E Speyer

Baker and Bowler showed that the Grassmannian can be defined over a tract, a field-like structure generalizing both partial fields and hyperfields. This notion unifies theories of matroids over partial fields, valuated matroids, and…

Combinatorics · Mathematics 2025-11-04 Donggyu Kim

This paper is about the combinatorics of finite point configurations in the tropical projective space or, dually, of arrangements of finitely many tropical hyperplanes. Moreover, arrangements of finitely many tropical halfspaces can be…

Combinatorics · Mathematics 2019-06-21 Michael Joswig , Georg Loho

While the positive Grassmannian is deeply understood through the rich combinatorics of plabic graphs and positroid cells, its tropical counterpart, the positive tropical Grassmannian Trop$_{>0}G(k,n)$, has lacked a comparable structural…

Combinatorics · Mathematics 2026-04-29 Nick Early , Thomas Lam

Let $\Lambda$ be a finite dimensional algebra over an algebraically closed field. Criteria are given which characterize existence of a fine or coarse moduli space classifying, up to isomorphism, the representations of $\Lambda$ with fixed…

Representation Theory · Mathematics 2014-07-11 Birge Huisgen-Zimmermann

We analyse the highest weight representations of the N=1 Ramond algebra and show that their structure is richer than previously suggested in the literature. In particular, we show that certain Verma modules over the N=1 Ramond algebra…

High Energy Physics - Theory · Physics 2009-10-31 Matthias Doerrzapf

Let $\mathbb{G}(d,n)$ be the complex Grassmannian of affine $d$-planes in $n$-space. We study the problem of characterizing the set of algebraic subvarieties of $\mathbb{G}(d,n)$ invariant under the action of the maximal torus $T$ and…

Algebraic Geometry · Mathematics 2025-03-10 E. Javier Elizondo , Alex Fink , Cristhian Garay López

We introduce the notion of a matroid M over a commutative ring R, assigning to every subset of the ground set an R-module according to some axioms. When R is a field, we recover matroids. When R=$\mathbb{Z}$, and when R is a DVR, we get…

Combinatorics · Mathematics 2019-11-19 Alex Fink , Luca Moci

We give an overview of recently implemented polymake features for computations in tropical geometry. The main focus is on explicit examples rather than technical explanations. Our computations employ tropical hypersurfaces, moduli of…

Algebraic Geometry · Mathematics 2018-10-30 Simon Hampe , Michael Joswig

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