activity
20192026
most citedRelative nonhomogeneous Koszul duality

7 citations · 9 across the 14 of their papers we have counts for

collaborators

14 papers

math.AG2026

The contraherent version of the theorem of Slavik and Stovicek

Leonid Positselski

This is a paper about contraherent cosheaves on non-semi-separated schemes. We prove two theorems, a negative one and a positive one. On the negative side, let be a quasi-compa…

math.RA2026

Homomorphisms of topological rings and change-of-scalar functors

Leonid Positselski

We consider homomorphisms of complete, separated right or two-sided linear topological rings with countable bases of neighborhoods of zero $\mathfrak f\colon\mathfrak R\to\mathfrak…

math.AG2026

Contraherent cosheaves of contramodules on Noetherian formal schemes

Leonid Positselski

There are two main results in this paper: the MGM equivalence between the conventional derived categories of abelian/exact categories, and the derived co-contra correspondence (i.e…

math.AC2025

Pseudo-dualizing complexes of torsion modules and semi-infinite MGM duality

Leonid Positselski

This paper is an MGM version of arXiv.org:1703.04266 and arXiv:1907.03364, and a follow-up to Section 5 of arXiv:1503.05523. In the setting of a commutative ring with a weakly…

math.CT2025

Coderived and contraderived categories for a cotorsion pair, flat-type cotorsion pairs, and relative periodicity

Leonid Positselski

Given a hereditary complete cotorsion pair generated by a set of objects in a Grothendieck category , we construct a natural equivalence between…

math.RA2025

A relative version of Bass' theorem about finite-dimensional algebras

Leonid Positselski

As a special case of Bass' theory of perfect rings, one obtains the assertion that, over a finite-dimensional associative algebra over a field, all flat modules are projective. In…

math.AC2025

Torsion modules and differential operators in infinitely many variables

Leonid Positselski

This paper grew out of the author's work on arXiv:2504.18460. Differential operators in the sense of Grothendieck acting between modules over a commutative ring can be interpreted…

math.AG2025

- duality on the contra side

Leonid Positselski

Given a smooth morphism of schemes , denote by the sheaf of rings of fiberwise crystalline differential operators on relative t…

math.CT2024

Compact generators of the contraderived category of contramodules

Leonid Positselski, Jan Stovicek

We consider the contraderived category of left contramodules over a right linear topological ring with a countable base of neighborhoods of zero. Equivalently, this i…

math.RA2024

A contramodule generalization of Neeman's flat and projective module theorem

Leonid Positselski

This paper builds on top of arXiv:2306.02734. We consider a complete, separated topological ring with a countable base of neighborhoods of zero consisting of open two…

math.AG2024★ 1 cited

Roos axiom holds for quasi-coherent sheaves

Leonid Positselski

Let be either a quasi-compact semi-separated scheme, or a Noetherian scheme of finite Krull dimension. We show that the Grothendieck abelian category of qua…

math.AG2023★ 1 cited

Philosophy of contraherent cosheaves

Leonid Positselski

Contraherent cosheaves are module objects over algebraic varieties defined by gluing using the colocalization functors. Contraherent cosheaves are designed to be used for globalizi…

math.CT2023

Semialgebras associated with nonunital algebras and -linear subcategories

Leonid Positselski

This paper is a sequel to arXiv:2307.13358 and arXiv:2308.16090. A construction associating a semialgebra with an algebra, subalgebra, and a coalgebra dual to the subalgebra played…

math.RA2019★ 7 cited

Relative nonhomogeneous Koszul duality

Leonid Positselski

This book contains a detailed exposition of the nonhomogeneous Koszul duality theory in the relative situation over a noncentral, noncommutative, nonsemisimple base ring, as announ…