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Related papers: Cluster Algebras and the Positive Grassmannian

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We introduce the notion of "binary" positive and complex geometries, giving a completely rigid geometric realization of the combinatorics of generalized associahedra attached to any Dynkin diagram. We also define open and closed "cluster…

High Energy Physics - Theory · Physics 2020-02-18 Nima Arkani-Hamed , Song He , Thomas Lam , Hugh Thomas

We study a class of quantized enveloping algebras, called twisted Yangians, associated with the symmetric pairs of types B, C, D in Cartan's classification. These algebras can be regarded as coideal subalgebras of the extended Yangian for…

Quantum Algebra · Mathematics 2016-09-21 Nicolas Guay , Vidas Regelskis

Scattering amplitudes in planar N=4 super Yang-Mills theory reveal a remarkable symmetry structure. In addition to the superconformal symmetry of the Lagrangian of the theory, the planar amplitudes exhibit a dual superconformal symmetry.…

High Energy Physics - Theory · Physics 2015-05-20 J. M. Drummond

We study skew-symmetrizable cluster algebras $\mathcal{A}$ associated with unpunctured surfaces $\tilde{\mathbf{S}}$ endowed with an orientation-preserving involution $\sigma$. We give a geometric realization of such cluster algebras by…

Representation Theory · Mathematics 2026-01-16 Azzurra Ciliberti

We consider (iced) quiver with potential $(\bar{Q}(D), F(D), \bar{W}(D))$ associated to a Postnilov Diagram $D$ and prove the mutation of the quiver with potential $(\bare{Q}(D), F(D), \bar{W}(D))$ is compatible with the geometric exchange…

Representation Theory · Mathematics 2021-03-05 Wen Chang , Jie Zhang

There is a cell decomposition of the nonnegative Grassmannian. For each cell, totally positive bases(TP-bases) is defined as the minimal set of Pl\"ucker variables such that all other nonzero Pl\"ucker variables in the cell can be expressed…

Combinatorics · Mathematics 2008-09-05 Suho OH

Let $H$ be a finite dimensional hereditary algebra over an algebraically closed field $k$ and $\mathscr{C}_{F^m}$ be the repetitive cluster category of $H$ with $m\geq 1$. We investigate the properties of cluster tilting objects in…

Representation Theory · Mathematics 2013-01-30 Shunhua Zhang , Yuehui Zhang

We consider algebras over a field K defined by a presentation K <x_1,..., x_n : R >, where $R$ consists of n choose 2 square-free relations of the form x_i x_j = x_k x_l with every monomial x_i x_j, i different from j, appearing in one of…

Rings and Algebras · Mathematics 2007-05-23 T. Gateva-Ivanova , Eric Jespers , Jan Okninski

We introduce the notion of a lower bound cluster algebra generated by projective cluster variables as a polynomial ring over the initial cluster variables and the so-called projective cluster variables. We show that under an acyclicity…

Representation Theory · Mathematics 2023-08-29 Karin Baur , Alireza Nasr-Isfahani

Gaetz, Pechenik, Pfannerer, Striker, and Swanson introduced the concept of hourglass plabic graphs and provided a method for computing web diagrams and invariants corresponding to $4\times n$ Young tableaux, while Elkin, Musiker, and Wright…

Combinatorics · Mathematics 2025-07-25 Wen Ting Zhang , Rui Zhi Tang , Jin Xing Zhao

This paper continues the study of cluster algebras initiated in math.RT/0104151. Its main result is the complete classification of the cluster algebras of finite type, i.e., those with finitely many clusters. This classification turns out…

Rings and Algebras · Mathematics 2015-06-26 Sergey Fomin , Andrei Zelevinsky

In 2013, Lee, Li, and Zelevinsky introduced combinatorial objects called compatible pairs to construct the greedy bases for rank-2 cluster algebras, consisting of indecomposable positive elements including the cluster monomials.…

Combinatorics · Mathematics 2024-09-24 Amanda Burcroff , Kyungyong Lee , Lang Mou

We consider two algebras of curves associated to an oriented surface of finite type - the cluster algebra from combinatorial algebra, and the skein algebra from quantum topology. We focus on generalizations of cluster algebras and…

Geometric Topology · Mathematics 2025-03-18 Hiroaki Karuo , Han-Bom Moon , Helen Wong

We describe all Poisson brackets compatible with the natural cluster algebra structure in the open Schubert cell of the Grassmannian $G_k(n)$ and show that any such bracket endows $G_k(n)$ with a structure of a Poisson homogeneous space…

Quantum Algebra · Mathematics 2016-05-25 Michael Gekhtman , Michael Shapiro , Alexander Stolin , Alek Vainshtein

We give a uniform geometric realization for the cluster algebra of an arbitrary finite type with principal coefficients at an arbitrary acyclic seed. This algebra is realized as the coordinate ring of a certain reduced double Bruhat cell in…

Rings and Algebras · Mathematics 2008-05-19 Shih-Wei Yang , Andrei Zelevinsky

We propose a novel graph clustering method guided by additional information on the underlying structure of the clusters (or communities). The problem is formulated as the matching of a graph to a template with smaller dimension, hence…

Machine Learning · Statistics 2021-07-06 Mateus Riva , Florian Yger , Pietro Gori , Roberto M. Cesar , Isabelle Bloch

Given a configuration $A$ of $n$ points in $\mathbb{R}^{d-1}$, we introduce the higher secondary polytopes $\Sigma_{A,1},\dots, \Sigma_{A,n-d}$, which have the property that $\Sigma_{A,1}$ agrees with the secondary polytope of…

Combinatorics · Mathematics 2019-09-13 Pavel Galashin , Alexander Postnikov , Lauren Williams

We address the appearance of algebraic singularities in the symbol alphabet of scattering amplitudes in the context of planar $\mathcal{N}=4$ super Yang-Mills theory. We argue that connections between cluster algebras and tropical geometry…

High Energy Physics - Theory · Physics 2019-12-19 James Drummond , Jack Foster , Ömer Gürdoğan , Chrysostomos Kalousios

We initiate the study of a class of polytopes, which we coin polypositroids, defined to be those polytopes that are simultaneously generalized permutohedra (or polymatroids) and alcoved polytopes. Whereas positroids are the matroids arising…

Combinatorics · Mathematics 2020-10-15 Thomas Lam , Alexander Postnikov

Let $R$ be a commutative ring with identity and a fixed invertible element $q^{\frac{1}{2}}$, and suppose $q+q^{-1}$ is invertible in $R$. For each planar surface $\Sigma_{0,n+1}$, we present its Kauffman bracket skein algebra over $R$ by…

Geometric Topology · Mathematics 2024-01-03 Haimiao Chen