English
Related papers

Related papers: Singular equivalence and the (Fg) condition

200 papers

For a finite quiver $Q$, we study the reachability category $\mathbf{Reach}_Q$. We investigate the properties of $\mathbf{Reach}_Q$ from both a categorical and a topological viewpoint. In particular, we compare $\mathbf{Reach}_Q$ with…

Rings and Algebras · Mathematics 2024-11-08 Luigi Caputi , Henri Riihimäki

Inspired by the properties of an $n$-frame of gradients $(\nabla f_1, \ldots, \nabla f_n)$ of a Morin map $f:M\rightarrow\mathbb{R}^n$, with $\dim M\geq n$, we introduce the notion of Morin singularities in the context of singular…

Geometric Topology · Mathematics 2016-08-03 Camila M. Ruiz

We give sufficient conditions for a Frobenius category to be equivalent to the category of Gorenstein projective modules over an Iwanaga-Gorenstein ring. We then apply this result to the Frobenius category of special Cohen-Macaulay modules…

Representation Theory · Mathematics 2019-02-20 Osamu Iyama , Martin Kalck , Michael Wemyss , Dong Yang

In this paper, we extend the study of graded equivalences to the case of general idempotent graded rings. We prove that the existence of a graded equivalence between two categories of graded torsion-free unital modules may be characterized…

Rings and Algebras · Mathematics 2026-04-15 Mikhailo Dokuchaev , Juan Jacobo Simón

We prove that the classes of graph algebras, Exel-Laca algebras, and ultragraph algebras coincide up to Morita equivalence. This result answers the long-standing open question of whether every Exel-Laca algebra is Morita equivalent to a…

Operator Algebras · Mathematics 2008-12-09 Takeshi Katsura , Paul S. Muhly , Aidan Sims , Mark Tomforde

Necessary and sufficient conditions are obtained for the uniqueness of standard regular AF masas in regular limit algebras up to approximate inner unitary equivalence.

Operator Algebras · Mathematics 2007-05-23 P. A. Haworth , Stephen Power

Let G < SL(V) be a finite group, V is finite dimensional over a field F, p=char F and S(V) is the symmetric algebra of V. We determine when the subring of G-invariants S(V)^G is a polynomial ring. As a consequence, we classify, if F is…

Commutative Algebra · Mathematics 2024-11-20 Amiram Braun

We prove that two finite-dimensional commutative algebras over an algebraically closed field are isomorphic if and only if they give rise to isomorphic representations of the category of finite sets and surjective maps.

Rings and Algebras · Mathematics 2011-04-05 S. S. Podkorytov

Let $\mathcal{A}= \{A_t \}_{t \in G}$ and $\mathcal{B}= \{B_t \}_{t\in G}$ be $C^*$-algebraic bundles over a finite group $G$. Let $C=\oplus_{t \in G}A_t$ and $D=\oplus_{t\in G}B_t$. Also, let $A=A_e$ and $B=B_e$, where $e$ is the unit…

Operator Algebras · Mathematics 2019-10-10 Kazunori Kodaka

The classical Morita Theorem for rings established the equivalence of three statements, involving categorical equivalences, isomorphisms between corners of finite matrix rings, and bimodule homomorphisms. A fourth equivalent statement…

Rings and Algebras · Mathematics 2022-05-17 Gene Abrams , Efren Ruiz , Mark Tomforde

We associate with every pure flag simplicial complex $\Delta$ a standard graded Gorenstein $\mathbb{F}$-algebra $R_{\Delta}$ whose homological features are largely dictated by the combinatorics and topology of $\Delta$. As our main result,…

Commutative Algebra · Mathematics 2023-05-09 Alessio D'Alì , Lorenzo Venturello

We show that infinitely many Gorenstein weakly-exceptional quotient singularities exist in all dimensions, we prove a weak-exceptionality criterion for five-dimensional quotient singularities, and we find a sufficient condition for being…

Algebraic Geometry · Mathematics 2012-05-25 Ivan Cheltsov , Constantin Shramov

We classify all $2$-blocks with abelian defect groups of rank $4$ up to Morita equivalence. The classification holds for blocks over a suitable discrete valuation ring as well as for those over an algebraically closed field. An application…

Group Theory · Mathematics 2024-09-16 Charles W. Eaton , Michael Livesey

We observe that a finitely generated algebraic algebra R (over a field) is finite dimensional if and only if the associated graded ring grR is right noetherian, if and only if grR has right Krull dimension, if and only if grR satisfies a…

Rings and Algebras · Mathematics 2017-08-14 Edward S. Letzter

We introduce Morita and Rickard equivalences over a group graded G-algebra between block extensions. A consequence of such equivalences is that Sp\"ath's central order relation holds between two corresponding character triples.

Representation Theory · Mathematics 2019-12-13 Andrei Marcus , Virgilius-Aurelian Minuta

This paper studies self-injective algebras of polynomial growth. We prove that the derived equivalence classification of weakly symmetric algebras of domestic type coincides with the classification up to stable equivalences (of Morita…

Representation Theory · Mathematics 2010-05-20 Guodong Zhou , Alexander Zimmermann

We describe cohomological conditions that are necessary and sufficient for the existence of balanced dualizing dg-modules, generalizing a theorem of Van den Bergh for balanced dualizing complexes over graded algebras. As a consequence, we…

Rings and Algebras · Mathematics 2025-06-04 Michael K. Brown , Andrew J. Soto Levins , Prashanth Sridhar

We study $F$-graded systems of ideals in $R$, which are sequences of ideals giving rise to Cartier algebras on $R$. We identify how properties of these systems (or modifications of these systems) affect the singularity properties of the…

Commutative Algebra · Mathematics 2026-05-25 Anna Brosowsky

In this paper we prove a general theorem about congruences between automorphic forms on a reductive group G which is compact at infinity modulo the center. If the rank is one, this essentially reduces to Ribet's level-raising theorem. We…

Number Theory · Mathematics 2016-09-07 Claus Mazanti Sorensen

For a discrete valuation ring $R$ with quotient field $K$ and residue field $F$ both of characteristic not 2, we study low-dimensional quadratic forms with Witt class in the $n$-th power of the fundamental ideal of $F$ resp. $K$ and point…

Number Theory · Mathematics 2024-04-23 Nico Lorenz
‹ Prev 1 3 4 5 6 7 10 Next ›