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Related papers: Exact completions and small sheaves

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We use the theory of approximable triangulated categories to give a condition for a proper DG-category to be reflexive in the sense of Kuznetsov and Shinder. To do this we provide another description of the completion of an approximable…

Algebraic Geometry · Mathematics 2025-05-16 Isambard Goodbody , Theo Raedschelders , Greg Stevenson

We extend the notion of regular coherence from rings to additive categories and show that well-known consequences of regular coherence for rings also apply to additive categories. For instance the negative K-groups and all twisted…

K-Theory and Homology · Mathematics 2025-04-02 Arthur Bartels , Wolfgang Lueck

Given a proper family of varieties over a smooth base, with smooth total space and general fibre, all over a finite field k with q elements, we show that a finiteness hypothesis on the Chow groups, CH_i, i=0,1,...,r, of the fibres in the…

Number Theory · Mathematics 2007-05-23 Najmuddin Fakhruddin

We describe the derived category of coherent sheaves on the minimal resolution of the Kleinian singularity associated to a finite subgroup G of SL(2). Then, we give an application to the Euler-characteristic version of the Hall algebra of…

Algebraic Geometry · Mathematics 2007-05-23 M. Kapranov , E. Vasserot

Let K be an abstract elementary classes which has arbitrarily large models and satisfies the amalgamation and joint embedding properties. Theorem 1. Suppose K is \chi-tame. If K is categorical in some \lambda^+ >LS(K) then it is categorical…

Logic · Mathematics 2007-05-23 Rami Grossberg , Monica VanDieren

We study degenerations of the Hall algebras of exact categories induced by degree functions on the set of isomorphism classes of indecomposable objects. We prove that each such degeneration of the Hall algebra $\mathcal{H}(\mathcal{E})$ of…

Representation Theory · Mathematics 2024-04-10 Xin Fang , Mikhail Gorsky

Using the Morita-type embedding, we show that any exact category with enough projectives has a realization as a (pre)resolving subcategory of a module category. When the exact category has enough injectives, the image of the embedding can…

Representation Theory · Mathematics 2019-07-30 Haruhisa Enomoto

This is a large audience version of our previous work (see math.AG/0301146) in which we prove the existence of an (exact) equivalence between the category of coherent analytic sheaves and the category of $\bar{\partial}$-coherent sheaves.…

Algebraic Geometry · Mathematics 2009-09-29 Nefon Pali

We consider a notion of exact sequences in any -not necessarily exact- pointed category relative to a given (E;M)-factorization structure. We apply this notion to introduce and investigate a new notion of exact sequences of semimodules over…

Category Theory · Mathematics 2011-11-03 Jawad Abuhlail

A problem of completing a linear map on C*-algebras to a completely positive map is analyzed. It is shown that whenever such a completion is feasible there exists a unique minimal completion. This theorem is used to show that under some…

Operator Algebras · Mathematics 2024-05-28 B. V. Rajarama Bhat , Arghya Chongdar

We prove that for any finite-dimensional differential graded algebra with separable semisimple part the category of perfect modules is equivalent to a full subcategory of the category of perfect complexes on a smooth projective scheme with…

Algebraic Geometry · Mathematics 2020-03-18 Dmitri Orlov

There is a well-known correspondence between coherent theories (and their interpretations) and coherent categories (resp. functors), hence the (2,1)-category $\mathbf{Coh_{\sim}}$ (of small coherent categories, coherent functors and all…

Category Theory · Mathematics 2021-04-28 Kristóf Kanalas

The goal of this papers is to extending to the complex analytic framework the relative Kleiman duality for quasi coherent sheaves. Precisely, he show that for any flat,locally projectivea and finitely presented morphism of schemes…

Algebraic Geometry · Mathematics 2024-06-17 Mohamed Kaddar

We define an equivalence relation among coherent sheaves on a projective variety called biliaison. We prove the existence of sheaves that are minimal in a biliaison class in a suitable sense, and show that all sheaves in the same class can…

Algebraic Geometry · Mathematics 2020-04-10 Mengyuan Zhang

We introduce the new concept of cartesian module over a pseudofunctor $R$ from a small category to the category of small preadditive categories. Already the case when $R$ is a (strict) functor taking values in the category of commutative…

Rings and Algebras · Mathematics 2015-05-27 Sergio Estrada , Simone Virili

We introduce and develop the model-theoretic notions of absolute connectedness and type-absolute connectedness for groups. We prove that groups of rational points of split semisimple linear groups (that is, Chevalley groups) over arbitrary…

Group Theory · Mathematics 2012-09-10 Jakub Gismatullin

Proto-exact and parabelian categories serve as non-additive analogues of exact and quasi-abelian categories, respectively. They give rise to algebraic K-theory and Hall algebras similarly to the additive setting. We show that every…

Representation Theory · Mathematics 2025-03-11 Sergey Mozgovoy

Adhesive categories are categories which have pushouts with one leg a monomorphism, all pullbacks, and certain exactness conditions relating these pushouts and pullbacks. We give a new proof of the fact that every topos is adhesive. We also…

Category Theory · Mathematics 2011-04-14 Stephen Lack

We generalize the definition of an exact sequence of tensor categories due to Brugui\`eres and Natale, and introduce a new notion of an exact sequence of (finite) tensor categories with respect to a module category. We give three…

Quantum Algebra · Mathematics 2015-04-07 Pavel Etingof , Shlomo Gelaki

The main goal of this paper is to prove that the idempotent completions of the triangulated categories of singularities of two schemes are equivalent if the formal completions of these schemes along singularities are isomorphic. We also…

Algebraic Geometry · Mathematics 2018-08-13 Dmitri Orlov