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We show that for any closed surface of genus greater than one and for any finite weighted graph filling the surface, there exists a hyperbolic metric which realizes the least Dirichlet energy harmonic embedding of the graph among a fixed…

Differential Geometry · Mathematics 2020-07-27 Toru Kajigaya , Ryokichi Tanaka

We first investigate the algebraic structure of vertex algebroids $B$ when $B$ are simple Leibniz algebras. Next, we use these vertex algebroids $B$ to construct indecomposable non-simple $C_2$-cofinite $\mathbb{N}$-graded vertex algebras…

Quantum Algebra · Mathematics 2020-11-25 Thuy Bui , Gaywalee Yamskulna

We compute the graded polynomial identities of the infinite dimensional upper triangular matrix algebra over an arbitrary field. If the grading group is finite, we prove that the set of graded polynomial identities admits a finite basis. We…

Rings and Algebras · Mathematics 2024-02-19 Micael Said Garcia , Felipe Yukihide Yasumura

We classify all complete uniform multipartite hypergraphs with respect to some algebraic properties, such as being (almost) complete intersection, Gorenstein, level, $l$-Cohen-Macaulay, $l$-Buchsbaum, unmixed, and satisfying Serre's…

Combinatorics · Mathematics 2014-02-14 Dariush Kiani , Sara Saeedi Madani

We prove a sharp upper bound on the number of distinct columns of a totally unimodular matrix with column sums $1$ improving upon Heller's classical bound. The proof uses Seymour's decomposition theorem. Such matrices are closely related to…

Combinatorics · Mathematics 2026-04-14 Benjamin Nill

Let $\mathfrak{g}$ be a Color Lie Algebra and $\mathcal{U}(\mathfrak{g})$ its the universal Enveloping Algebra. We define the notion of graded deformations and we give explicit graded deformations of the universal Enveloping Algebra of…

Rings and Algebras · Mathematics 2025-12-09 Toukaiddine Petit

A theory of graded manifolds can be viewed as a generalization of differential geometry of smooth manifolds. It allows one to work with functions which locally depend not only on ordinary real variables, but also on $\mathbb{Z}$-graded…

Differential Geometry · Mathematics 2023-03-14 Jan Vysoky

We introduce the notion of vertex coalgebra, a generalization of vertex operator coalgebras. Next we investigate forms of cocommutativity, coassociativity, skew-symmetry, and an endomorphism, $D^*$, which hold on vertex coalgebras. The…

Quantum Algebra · Mathematics 2008-01-22 Keith Hubbard

We prove that the vertices of every $(r + 1)$-uniform hypergraph with maximum degree $\Delta$ may be coloured with $c(\frac{\Delta}{d + 1})^{1/r}$ colours such that each vertex is in at most $d$ monochromatic edges. This result, which is…

Combinatorics · Mathematics 2022-08-17 António Girão , Freddie Illingworth , Alex Scott , David R. Wood

First we prove that any inner automorphism in the stabilizer of a graded-simple unital associative algebra whose grading group is abelian is the conjugation by a homogeneous element. Now consider a grading by an abelian group on an…

Rings and Algebras · Mathematics 2023-10-12 Adrián Rodrigo-Escudero

We introduce a monomial ideal whose standard monomials encode the vertices of all fibers of a lattice. We study the minimal generators, the radical, the associated primes and the primary decomposition of this ideal, as well as its relation…

Combinatorics · Mathematics 2007-05-23 Serkan Hosten , Diane Maclagan

We show that the mixed volumes of arbitrary convex bodies are equal to mixed multiplicities of graded families of monomial ideals, and to normalized limits of mixed multiplicities of monomial ideals. This result evinces the close relation…

Commutative Algebra · Mathematics 2021-02-18 Yairon Cid-Ruiz , Jonathan Montaño

Given an ample, Hausdorff groupoid $\mathcal{G}$, and a unital commutative ring $R$, we consider the Steinberg algebra $A_R(\mathcal {G})$. First we prove a uniqueness theorem for this algebra and then, when $\mathcal{G}$ is graded by a…

Rings and Algebras · Mathematics 2016-09-12 Lisa Orloff Clark , Ruy Exel , Enrique Pardo

For a undirected simple graph $G$, let $d_i(G)$ be the number of $i$-element dominating vertex set of $G$. The domination polynomial of the graph $G$ is defined as $$D(G, x) = \sum_{i = 1}^n d_i(G)x^i.$$ Alikhani and Peng conjectured that…

Combinatorics · Mathematics 2021-11-03 Shengtong Zhang

A graph $G$ is called well-covered if all maximal independent sets of vertices have the same cardinality. A simplicial complex $\Delta$ is called pure if all of its facets have the same cardinality. Let $\mathcal G$ be the class of graphs…

Commutative Algebra · Mathematics 2012-07-11 Rashid Zaare-Nahandi

This article concerns commutative algebras over a field $k$ of characteristic zero which are finite dimensional as vectorspaces, and particularly those of such algebras which are graded. Here the term graded is applied to non-negatively…

Algebraic Geometry · Mathematics 2011-08-29 Guillermo Cortiñas , Fabiana Krongold

We determine the minimum degree sum of two adjacent vertices that ensures a perfect matching in a 3-graph without isolated vertex. More precisely, suppose that $H$ is a 3-uniform hypergraph whose order $n$ is sufficiently large and…

Combinatorics · Mathematics 2017-10-16 Yi Zhang , Yi Zhao , Mei Lu

In this paper, we consider partially commutative metabelian Lie algebras whose defining graphs are cycles. We show that such algebras are universally equivalent iff the corresponding cycles have the same length. Moreover, we give an example…

Rings and Algebras · Mathematics 2013-05-27 Evgeny Poroshenko

We give characterizations of the structure and degree sequences of hereditary unigraphs, those graphs for which every induced subgraph is the unique realization of its degree sequence. The class of hereditary unigraphs properly contains the…

Combinatorics · Mathematics 2015-08-04 Michael D. Barrus

We give new characterizations for the class of uniformly dense matroids and study applications of these characterizations to graphic and real representable matroids. We show that a matroid is uniformly dense if and only if its base polytope…

Combinatorics · Mathematics 2026-02-03 Karel Devriendt , Raffaella Mulas
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