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We initiate a study of tensor ideals in linear rigid monoidal categories that are kernels of linear monoidal functors to abelian monoidal categories. We develop general methods and apply them to the category of tilting modules over quantum…

Quantum Algebra · Mathematics 2025-12-02 Kevin Coulembier , Pavel Etingof , Victor Ostrik

Let $R$ be a discrete valuation ring with fraction field $K$ and $X$ a flat $R$-scheme. Given a faithful action of a $K$-group scheme $G_K$ over the generic fibre $X_K$, we study models $G$ of $G_K$ acting on $X$. In various situations, we…

Algebraic Geometry · Mathematics 2009-10-07 Matthieu Romagny

We show that the Kazhdan-Lusztig category $KL_k$ of level-$k$ finite-length modules with highest-weight composition factors for the affine Lie superalgebra $\widehat{\mathfrak{gl}(1|1)}$ has vertex algebraic braided tensor supercategory…

Quantum Algebra · Mathematics 2022-08-15 Thomas Creutzig , Robert McRae , Jinwei Yang

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…

We give a complete classification of the irreducible quasifinite modules for algebras of the form Vir \otimes A, where Vir is the Virasoro algebra and A is a Noetherian commutative associative unital algebra over the complex numbers. It is…

Representation Theory · Mathematics 2012-05-21 Alistair Savage

We show that the braided tensor category of finitely-generated weight modules for the simple affine vertex operator algebra $L_k(\mathfrak{sl}_2)$ of $\mathfrak{sl}_2$ at any admissible level $k$ is rigid and hence a braided ribbon…

Quantum Algebra · Mathematics 2024-11-19 Thomas Creutzig , Robert McRae , Jinwei Yang

Let $k$ be an algebraically closed field of characteristic $p\ge 0$. Let $G$ be an affine group scheme over $k$. We classify the indecomposable exact module categories over the rigid tensor category $\text{Coh}_f(G)$ of coherent sheaves of…

Quantum Algebra · Mathematics 2013-01-22 Shlomo Gelaki

Recently the author has studied rings for which products of flat modules have finite flat dimension. In this paper we extend the theory to characterize when products of modules in $\mathcal T$ have finite $\mathcal T$-projective dimension,…

Rings and Algebras · Mathematics 2019-07-18 Manuel Cortés Izurdiaga

We classify all tilting and cotilting classes over commutative noetherian rings in terms of descending sequences of specialization closed subsets of the Zariski spectrum. Consequently, all resolving subcategories of finitely generated…

Commutative Algebra · Mathematics 2014-06-03 Lidia Angeleri Hügel , David Pospisil , Jan Stovicek , Jan Trlifaj

We establish a bijection between torsion pairs in the category of finite-dimensional modules over a finite-dimensional algebra A and pairs (Z, I) formed by a closed rigid set Z in the Ziegler spectrum of A and a set I of indecomposable…

Representation Theory · Mathematics 2024-03-04 Lidia Angeleri Hügel , Rosanna Laking , Francesco Sentieri

We study exact module categories over the representation categories of finite-dimensional quasi-Hopf algebras. As a consequence we classify exact module categories over some families of pointed tensor categories with cyclic group of…

Quantum Algebra · Mathematics 2011-09-12 César Galindo , Martín Mombelli

In the first part, we further advance the study of category theory in a strong balanced factorization category C [Pisani, 2008], a finitely complete category endowed with two reciprocally stable factorization systems such that X \to 1 is in…

Category Theory · Mathematics 2009-04-27 Claudio Pisani

For a quantum affine algebra of type A, we describe the composition series of the tensor product of a general minimal affinization with a Kirillov-Resehtikhin module associated to an extreme node of the Dynkin diagram of the underlying…

Representation Theory · Mathematics 2017-12-19 Adriano Moura , Fernanda Pereira

Let $X$ be a reduced connected $k$-scheme pointed at a rational point $x \in X(k)$. By using tannakian techniques we construct the Galois closure of an essentially finite $k$-morphism $f:Y\to X$ satisfying the condition…

Algebraic Geometry · Mathematics 2012-09-19 Marco Antei , Michel Emsalem

We consider deformations of bounded complexes of modules for a profinite group G over a field of positive characteristic. We prove a finiteness theorem which provides some sufficient conditions for the versal deformation of such a complex…

Number Theory · Mathematics 2013-09-03 Frauke M. Bleher , Ted Chinburg

A finite tensor category is called pointed if all its simple objects are invertible. We find necessary and sufficient conditions for two pointed semisimple categories to be dual to each other with respect to a module category. Whenever the…

Quantum Algebra · Mathematics 2009-12-19 Deepak Naidu

Let $\mathcal{E}$ be a weakly idempotent complete exact category with enough injective and projective objects. Assume that $\mathcal{M} \subseteq \mathcal{E}$ is a rigid, contravariantly finite subcategory of $\mathcal{E}$ containing all…

Representation Theory · Mathematics 2019-05-07 Lucie Jacquet-Malo

Let $A$ be an artinian algebra, and let $\mathcal{C}$ be a subcategory of mod$A$ that is closed under extensions. When $\mathcal{C}$ is closed under kernels of epimorphisms (or closed under cokernels of monomorphisms), we describe the…

Representation Theory · Mathematics 2015-05-27 François Huard , Marcelo Lanzilotta , David Smith

Let A be a commutative ring, and \a a weakly proregular ideal in A. This includes the noetherian case: if A is noetherian then any ideal in it is weakly proregular; but there are other interesting examples. In this paper we prove the MGM…

Commutative Algebra · Mathematics 2012-10-17 Marco Porta , Liran Shaul , Amnon Yekutieli

This paper is a major step in the classification of endotrivial modules over p-groups. Let G be a finite p-group and k be a field of characteristic p. A kG-module M is an endo-trivial module if {\End_k(M)\cong k\oplus F} as kG-modules,…

Group Theory · Mathematics 2007-06-28 Jon F. Carlson , Jacques Thevenaz