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Let R be a commutative, noetherian, local ring. Topological Q-vector spaces modelled on full subcategories of the derived category of R are constructed in order to study intersection multiplicities.

Commutative Algebra · Mathematics 2007-05-23 Anders J. Frankild , Esben Bistrup Halvorsen

Holm (H. Holm, Modules with cosupport and injective functors, Algebr. Represent. Theor., 13 (2010), 543-560) considers categories of right modules dual to those with support in a set of finitely presented modules. We extend some of his…

Representation Theory · Mathematics 2013-04-17 Akeel Ramadan Mehdi , Mike Prest

For any good tilting module $T$ over a ring $A$, there exists an $n$-symmetric subcategory $\mathscr{E}$ of a module category such that the derived category of the endomorphism ring of $T$ is a recollement of the derived categories of…

Representation Theory · Mathematics 2021-06-11 Hongxing Chen , Changchang Xi

We compare closed and rigid monoidal categories. Closedness is defined by the tensor product having a right adjoint: the internal hom functor. Rigidity, on the other hand, generalises the duality of finite-dimensional vector spaces. In the…

Category Theory · Mathematics 2026-02-06 Sebastian Halbig , Tony Zorman

Definable subcategories may be extended along a ring homomorphism directly, by using their defining conditions in the new module category, or by tensoring up with the new ring. We investigate what is preserved and reflected by these…

Representation Theory · Mathematics 2026-03-31 Mike Prest

Let $M$ be a $G$-manifold and $\om$ a $G$-invariant exact $m$-form on $M$. We indicate when these data allow us to constract a cocycle on a group $G$ with values in the trivial $G$-module $\mathbb R$ and when this cocycle is nontrivial.

Differential Geometry · Mathematics 2015-06-26 Mark Losik , Peter W. Michor

Auslander-Reiten duality for module categories is generalised to Grothendieck abelian categories that have a sufficient supply of finitely presented objects. It is shown that Auslander-Reiten duality amounts to the fact that the functor…

Representation Theory · Mathematics 2016-04-12 Henning Krause

Covariant Hom-bimodules are introduced and the structure theory of them in the Hom-setting is studied in a detailed way. The category of bicovariant Hom-bimodules is proved to be a (pre)braided monoidal category and its structure theory is…

Quantum Algebra · Mathematics 2019-05-28 Serkan Karaçuha

A topological commutative ring is said to be rigid when for every set $X$, the topological dual of the $X$-fold topological product of the ring is isomorphic to the free module over $X$. Examples are fields with a ring topology, discrete…

Commutative Algebra · Mathematics 2018-08-21 Laurent Poinsot

If (A,B) and (A',B') are co-t-structures of a triangulated category, then (A',B') is called intermediate if A \subseteq A' \subseteq \Sigma A. Our main results show that intermediate co-t-structures are in bijection with two-term silting…

Representation Theory · Mathematics 2015-04-22 Osamu Iyama , Peter Jorgensen , Dong Yang

It is proved that for a commutative noetherian ring with dualizing complex the homotopy category of projective modules is equivalent, as a triangulated category, to the homotopy category of injective modules. Restricted to compact objects,…

Commutative Algebra · Mathematics 2007-05-23 Srikanth Iyengar , Henning Krause

Let R be a commutative ring with identity and M be an R-module. The purpose of this paper is to introduced the dual notion of z-submodules of M and some of extensions. Moreover, we investigate some properties of these classes of modules…

Commutative Algebra · Mathematics 2023-09-19 F. Farshadifar , A. Molkhasi , E. Nazari

This works concerns cohomological support varieties of modules over commutative local rings. The main result is that the support of a derived tensor product of a pair of differential graded modules over a Koszul complex is the join of the…

Commutative Algebra · Mathematics 2022-03-15 Srikanth B. Iyengar , Josh Pollitz , William T. Sanders

We define the Hochschild complex and cohomology of a ring object in a monoidal category enriched over abelian groups. We interpret the cohomology groups and prove that the cohomology ring is graded-commutative.

Category Theory · Mathematics 2022-01-25 Magnus Hellstrøm-Finnsen

Given any commutative Noetherian ring $R$ and an element $x$ in $R$, we consider the full subcategory $\C(x)$ of its singularity category consisting of objects for which the morphism that is given by the multiplication by $x$ is zero. Our…

Commutative Algebra · Mathematics 2023-06-26 Özgür Esentepe , Ryo Takahashi

All rings considered are commutative. In this article we introduce and study two notions of modules which are stronger than CS modules, namely weakly IN modules and strongly CS modules. Our main aim is to characterize when a trivial…

Rings and Algebras · Mathematics 2021-12-21 Farid Kourki , Rachid Tribak

The representation theory of a conformal net is a unitary modular tensor category. It is captured by the bimodule category of the Jones-Wassermann subfactor. In this paper, we construct multi-interval Jones-Wassermann subfactors for unitary…

Operator Algebras · Mathematics 2017-06-09 Zhengwei Liu , Feng Xu

We show that a triangulated motivic category admits categorical Thom isomorphisms for vector bundles with an additional structure if and only if the generalized motivic cohomology theory represented by the tensor unit object admits Thom…

Algebraic Topology · Mathematics 2021-08-25 Alexey Ananyevskiy

We show that contrary to appearances, Multimodal Type Theory (MTT) over a 2-category M can be interpreted in any M-shaped diagram of categories having, and functors preserving, M-sized limits, without the need for extra left adjoints. This…

Category Theory · Mathematics 2024-02-14 Michael Shulman

A non-unital algebra in a closed monoidal category is called self-induced if the multiplication induces an isomorphism between A\otimes_A A and A. For such an algebra, we define smoothening and roughening functors that retract the category…

Rings and Algebras · Mathematics 2015-10-23 Ralf Meyer