English
Related papers

Related papers: Shard modules

200 papers

The existence of stable ACM vector bundles of high rank on algebraic varieties is a challenging problem. In this paper, we study stable Ulrich bundles (that is, stable ACM bundles whose corresponding module has the maximum number of…

Algebraic Geometry · Mathematics 2011-05-06 Marta Casanellas , Robin Hartshorne

Let R be an affine algebra of dimension n \geq 3 over an algebraically closed field k. Suppose char k =0 or char k =p \geq n. Let g,f_1,...,f_r be a R-regular sequence and A=R[f_1/g,...,f_r/g]. Let P be a projective A-module of rank n-1…

Commutative Algebra · Mathematics 2007-05-23 Manoj Kumar Keshari

Let $R$ be an algebra over a ring $\Bbbk$, $T$ an $R$-algebra, $M$ a finitely generated projective $R$-module, and $N$ a $T$-module. Let $G$ be a linearly reductive group scheme over $\Bbbk$ equipped with a representation…

Unstable modules over the Steenrod algebra with only the top $k$ operations are introduced in the language of ringoids. We prove the category of such modules has homological dimension at most $k$. A pratical method, which generalizes the…

Algebraic Topology · Mathematics 2022-01-05 Zhulin Li

We prove a characterization of profinite algebras, i.e., topological algebras that are isomorphic to a projective limit of finite discrete algebras. In general profiniteness concerns both the topological and algebraic characteristics of a…

Logic · Mathematics 2020-08-25 Friedrich Martin Schneider , Jens Zumbrägel

Let $\mathbf{k}$ be an algebraically closed field. Recently, K. Erdmann classified the symmetric $\mathbf{k}$-algebras $\Lambda$ of finite representation type such that every non-projective module $M$ has period dividing four. The goal of…

Representation Theory · Mathematics 2024-06-19 Jhony F. Caranguay-Mainguez , Pedro Rizzo , Jose A. Velez-Marulanda

In this paper, we first show that for an acyclic gentle algebra A, the irreducible components of any moduli space of A-modules are products of projective spaces. Next, we show that the nice geometry of the moduli spaces of modules of an…

Representation Theory · Mathematics 2014-07-30 Andrew T. Carroll , Calin Chindris

We study cluster tilting modules in mesh algebras of Dynkin type, providing a new proof for their existence. In all but one case, we show that these are precisely the maximal rigid modules, and that they are equivariant for a certain…

Representation Theory · Mathematics 2020-07-03 Karin Erdmann , Sira Gratz , Lisa Lamberti

For a finite group acting on a polynomial ring, the Chevalley-Shephard-Todd Theorem proves that the fixed subring is isomorphic to a polynomial ring if and only if the group is generated by pseudo-reflections. In recent years, progress was…

Rings and Algebras · Mathematics 2018-10-25 Stephan Weispfenning

We study self-extensions of modules over symmetric artin algebras. We show that non-projective modules with eventually vanishing self-extensions must lie in AR components of stable type $\mathbb{Z}A_{\infty}$. Moreover, the degree of the…

Representation Theory · Mathematics 2013-11-11 Kosmas Diveris , Marju Purin

This paper deals with stratifying systems over hereditary algebras. In the case of tame hereditary algebras we obtain a bound for the size of the stratifying systems composed only by regular modules and we conclude that stratifying systems…

Representation Theory · Mathematics 2013-08-27 Paula A. Cadavid , Eduardo do N. Marcos

We study the structure of the $0$-Schur algebra $S_0(n, r)$ following the geometric construction of $S_0(n, r)$ by Jensen and Su \cite{JS}. The main results are the construction and classification of indecomposable projective modules. In…

Rings and Algebras · Mathematics 2016-01-01 Bernt Tore Jensen , Xiuping Su , Guiyu Yang

We provide a unified approach, via deformations of incidence algebras, to several important types of representations with finiteness conditions, as well as the combinatorial algebras which produce them. We show that over finite dimensional…

Representation Theory · Mathematics 2018-05-07 Miodrag C. Iovanov , Gerard D. Koffi

We introduce (n+1)-preprojective algebras of algebras of global dimension n. We show that if an algebra is n-representation-finite then its (n+1)-preprojective algebra is self-injective. In this situation, we show that the stable module…

Representation Theory · Mathematics 2011-04-21 Osamu Iyama , Steffen Oppermann

As a natural generalization quantum Schur algebras associated with the Hecke algebra of the symmetric group, we introduce the quantum Schur superalgebra of type Q associated with the Hecke-Clifford superalgebra, which, by definition, is the…

Representation Theory · Mathematics 2018-02-26 Jie Du , Jinkui Wan

Skein modules are the main objects of an algebraic topology based on knots (or position). In the same spirit as Leibniz we would call our approach "algebra situs." When looking at the panorama of skein modules we see, past the rolling hills…

Geometric Topology · Mathematics 2007-05-23 Jozef H. Przytycki

The aim of this paper is two--fold. We first strongly improve our previous main result Theorem 3.1 in Arxiv 1702.00918v3 12Feb2018 ("Brill-Noether loci of rank two vector bundles on a general $\nu$-gonal curve"), concerning classification…

Algebraic Geometry · Mathematics 2018-09-07 Youngook Choi , Flaminio Flamini , Seonja Kim

Let X be a geometrically irreducible smooth projective curve over a field k. We describe the algebra of endomorphisms of indecomposable unstable vector bundles over X of rank 2 and degree d. Fixing some numerical invariants, namely the…

Algebraic Geometry · Mathematics 2011-03-01 L. Brambila-Paz , Osbaldo Mata , Nitin Nitsure

We prove a new kind of homological stability theorem for automorphism groups of finitely-generated projective modules over Dedekind domains, which takes into account all possible stabilisation maps between these, rather than only…

Commutative Algebra · Mathematics 2024-05-14 Oscar Randal-Williams

In this paper we study stable finiteness of ample groupoid algebras with applications to inverse semigroup algebras and Leavitt path algebras, recovering old results and proving some new ones. In addition, we develop a theory of (faithful)…

Rings and Algebras · Mathematics 2025-10-24 Benjamin Steinberg