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Related papers: Universally Koszul algebras defined by graphs

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We introduce a class of algebras over a field $\mathbb{F}$ related to directed graphs in which all edges are labeled by nonzero elements of the field $\mathbb{F}$. If all labels are different from $1$, these algebras are axial algebras. We…

Commutative Algebra · Mathematics 2026-03-05 Hans Cuypers

We provide a characterisation of all graphs whose parity binomial edge ideals have pure resolutions. In particular, we show that the minimal free resolution of a parity binomial edge ideal is pure if and only if the corresponding graph is a…

Commutative Algebra · Mathematics 2020-11-17 Peter Phelan

In this paper we prove that if G is a connected, simply-connected, semi-simple algebraic group over an algebraically closed field of sufficiently large characteristic, then all the blocks of the restricted enveloping algebra (Ug)_0 of the…

Representation Theory · Mathematics 2019-12-19 Simon Riche

A graph is universally $k$-edge-weightable if for every $k$-element set $Q\subset\mathbb{R}$, it admits a proper $Q$-edge weighting. The settled 1-2-3 conjecture implies that for any arithmetic progression $\{a,b,c\}$, every nice regular…

Combinatorics · Mathematics 2026-02-16 Kecai Deng

Koszul algebras have arisen in many contexts; algebraic geometry, combinatorics, Lie algebras, non-commutative geometry and topology. The aim of this paper and several sequel papers is to show that for any finite dimensional algebra there…

Category Theory · Mathematics 2014-12-17 Roberto Martinez-Villa , Øyvind Solberg

We study absolutely Koszul algebras, Koszul algebras with the Backelin-Roos property and their behavior under standard algebraic operations. In particular, we identify some Veronese subrings of polynomial rings that have the Backelin-Roos…

Commutative Algebra · Mathematics 2014-12-01 Aldo Conca , Srikanth B. Iyengar , Hop D. Nguyen , Tim Römer

Every $K_4$-free graph on $n$ vertices has a set of $\lfloor n/2\rfloor$ vertices spanning at most $n^2/18$ edges.

Combinatorics · Mathematics 2024-10-08 Christian Reiher

Let $A$ be a bi-Koszul algebra, we describe all possible $A_\infty$-algebra structures on the Ext-algebra $E(A)$, and prove that $E(A)$ must be $[m_2, m_3]$-finitely generated. An equivalent description for a connected graded algebra to be…

Rings and Algebras · Mathematics 2009-03-31 J. -R. Si , D. -M. Lu

We give a sufficient condition on totally disconnected topological graphs such that their associated topological graph algebras are purely infinite.

Operator Algebras · Mathematics 2017-03-31 Hui Li

A differential graded (DG for short) free algebra $\mathcal{A}$ is a connected cochain DG algebra such that its underlying graded algebra is $$\mathcal{A}^{\#}=\k\langle x_1,x_2,\cdots, x_n\rangle,\,\, \text{with}\,\, |x_i|=1,\,\, \forall…

Rings and Algebras · Mathematics 2018-05-08 X. -F. Mao , J. -F. Xie , Y. -N. Yang , Almire. Abla

Absolutely Koszul algebras are a class of rings over which any finite graded module has a rational Poincar\'e series. We provide a criterion to detect non-absolutely Koszul rings. Combining the criterion with machine computations, we…

Commutative Algebra · Mathematics 2017-04-26 Hop D. Nguyen

We propose a new definition of Koszulity for graded algebras where the degree zero part has finite global dimension, but is not necessarily semi-simple. The standard Koszul duality theorems hold in this setting. We give an application to…

Representation Theory · Mathematics 2010-07-21 Dag Madsen

The algebras $A(\Gamma)$, where $\Gamma$ is a directed layered graph, were first constructed by I. Gelfand, S. Serconek, V. Retakh and R. Wilson. These algebras are generalizations of the algebras $Q_n$, which are related to factorizations…

Quantum Algebra · Mathematics 2012-04-23 David Nacin

For distinct vertices $u,v$ in a graph $G$, let $\kappa_G(u,v)$ denote the maximum number of internally disjoint $u$-$v$ paths in $G$. Then, $\kappa_G(u,v) \leq \min\{ \mbox{deg}_G(u), \mbox{deg}_G(v) \}$. If equality is attained for every…

Combinatorics · Mathematics 2025-10-02 Richter Jordaan

We show that the existence of a universal structure implies the existence of a generic structure for any approximable class $\mathcal{C}$ of countable structures. We also show that the converse is not true. As a consequence, we provide…

Logic · Mathematics 2022-06-23 Aristotelis Panagiotopoulos , Katrin Tent

We develop a curved Koszul duality theory for algebras presented by quadratic-linear-constant relations over unital versions of binary quadratic operads. As an application, we study Poisson $n$-algebras given by polynomial functions on a…

Algebraic Topology · Mathematics 2022-09-07 Najib Idrissi

We introduce a notion of Koszul A-infinity algebra that generalizes Priddy's notion of a Koszul algebra and we use it to construct small A-infinity algebra models for Hochschild cochains. As an application, this yields new techniques for…

Algebraic Topology · Mathematics 2017-11-20 Alexander Berglund , Kaj Börjeson

Let $R$ be a positively graded algebra over a field. We say that $R$ is Hilbert-cyclotomic if the numerator of its reduced Hilbert series has all of its roots on the unit circle. Such rings arise naturally in commutative algebra, numerical…

Commutative Algebra · Mathematics 2021-06-10 Alessio Borzì , Alessio D'Alì

The algebras $Q_n$ describe the relationship between the roots and coefficients of a non-commutative polynomial. I.Gelfand, S.Gelfand, and V. Retakh have defined quotients of these algebras corresponding to graphs. In this work we find the…

Quantum Algebra · Mathematics 2007-05-23 David Nacin

We will describe how we can identify the structure of the Koszul algebra for trivariate monomial ideals from minimal free resolutions. We use recent work of L. Avramov, where he classifies the behavior of Bass numbers of embedding codepth 3…

Commutative Algebra · Mathematics 2013-03-04 Jared Painter