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Comparing vanishing of local cohomology in zero and positive characteristic, we give an example of a D-module on a Grassmann variety in positive characteristic with non-vanishing first cohomology group. This is a counterexample to…

Algebraic Geometry · Mathematics 2007-06-13 Masaki Kashiwara , Niels Lauritzen

This paper continues the investigation of quasilength, of content of local cohomology with respect to generators of the support ideal, and of robust algebras begun in joint work of Hochster and Huneke. We settle several questions raised by…

Commutative Algebra · Mathematics 2016-09-23 Mel Hochster , Wenliang Zhang

Consider the middle perversity intersection cohomology groups of various compactifications of a Hermitian locally symmetric space. Rapoport and independently Goresky and MacPherson have conjectured that these groups coincide for the…

Representation Theory · Mathematics 2007-05-23 Leslie Saper

We show how finiteness properties of a group and a subgroup transfer to finiteness properties of the Schlichting completion relative to this subgroup. Further, we provide a criterion when the dense embedding of a discrete group into the…

Group Theory · Mathematics 2026-01-14 Laura Bonn , Roman Sauer

In a previous paper, the authors showed that the category of E(n)_*E(n)-comodules is a localization of the category of BP_*BP-comodules. In this paper, we study the resulting localization functor L_n on the category of BP_*BP-comodules. It…

Algebraic Topology · Mathematics 2007-05-23 Mark Hovey , Neil Strickland

We compute support of formal cohomology modules in a serial of non-trivial cases. Applications are given. For example, we compute injective dimension of certain local cohomology modules in terms of dimension of their's support.

Commutative Algebra · Mathematics 2018-08-15 Mohsen Asgharzadeh

We use Cox's description for sheaves on toric varieties and results about the local cohomology with respect to monomial ideals to give a characteristic free approach to vanishing results on arbitrary toric varieties. As an application, we…

Algebraic Geometry · Mathematics 2007-05-23 Mircea Mustata

We find conditions on the local cohomology modules of multi-Rees algebras of admissible filtrations which enable us to predict joint reduction numbers. As a consequence we are able to prove a generalisation of a result of…

Commutative Algebra · Mathematics 2016-03-08 Parangama Sarkar , J. K. Verma

For a fixed ring, different classes of ring epimorphisms and localisation maps are compared. In fact, we provide sufficient conditions for a ring epimorphism to be a universal localisation. Furthermore, we consider recollements induced by…

Rings and Algebras · Mathematics 2012-07-20 Frederik Marks , Jorge Vitoria

Let Q be an affine semigroup generating Z^d, and fix a finitely generated Z^d-graded module M over the semigroup algebra k[Q] for a field k. We provide an algorithm to compute a minimal Z^d-graded injective resolution of M up to any desired…

Commutative Algebra · Mathematics 2007-05-23 David Helm , Ezra Miller

We consider tautological bundles and their exterior and symmetric powers on the Quot scheme over the projective line. We prove and conjecture several statements regarding the vanishing of their higher cohomology, and we describe their…

Algebraic Geometry · Mathematics 2026-05-13 Alina Marian , Dragos Oprea , Steven V Sam

We study the preservation of semisimplicity for holonomic D-modules with respect to the direct and inverse image of mainly finite maps $\pi : X \to Y$ of smooth varieties. A natural filtration of the direct image $\pi_+({\mathcal O}_X)$ is…

Algebraic Geometry · Mathematics 2018-11-19 Rolf Källström

Matlis duals of local cohomology modules are investigated with respect to many different topics (see section 0 - Introduction). One of these topics are complete intersections - see Corollary 1.1.4.

Commutative Algebra · Mathematics 2007-05-23 Michael Hellus

There are a large number of theorems detailing the homological properties of the Stanley--Reisner ring of a simplicial complex. Here we attempt to generalize some of these results to the case of a simplicial poset. By investigating the…

Commutative Algebra · Mathematics 2017-10-17 Connor Sawaske

The purpose of this paper is to study local cohomology in the noncommutative algebraic geometry framework of Artin and Zhang. The noncommutative spaces are obtained by base change of a Grothendieck category that is locally noetherian or…

Category Theory · Mathematics 2023-09-26 Abhishek Banerjee , Surjeet Kour

In this paper we study the local cohomology of all finitely generated bigraded modules over a standard bigraded polynomial ring which have only one nonvanishing local cohomology with respect to one of the irrelevant bigraded ideals.

Commutative Algebra · Mathematics 2008-03-25 Ahad Rahimi

The goal of this note is to record the following curious fact: let $(S,\n)$ be an unramified regular local ring of mixed characteristic $p>0$ and dimension $d$. Let $L$ denote the quotient field of $S$ and $K=L(\omega)$ with $\omega^p\in…

Commutative Algebra · Mathematics 2026-04-29 Prashanth Sridhar

Let $A$ be a commutative Noetherian ring of characteristic zero and $R=A[X_1, \ldots, X_d]$ be a polynomial ring over $A$ with the standard $\mathbb{N}^d$-grading. Let $I\subseteq R$ be an ideal which can be generated by elements of the…

Commutative Algebra · Mathematics 2023-07-10 Tony J. Puthenpurakal , Sudeshna Roy

We compute the local cohomology modules H_Y^(X,O_X) in the case when X is the complex vector space of n x n symmetric, respectively skew-symmetric matrices, and Y is the closure of the GL-orbit consisting of matrices of any fixed rank, for…

Commutative Algebra · Mathematics 2017-08-15 Claudiu Raicu , Jerzy Weyman

For positive integers m >= n >= p, we compute the GL_m x GL_n-equivariant description of the local cohomology modules of the polynomial ring S of functions on the space of m x n matrices, with support in the ideal of p x p minors. Our…

Algebraic Geometry · Mathematics 2015-07-24 Claudiu Raicu , Jerzy Weyman