Let A be a regular ring containing field of characteristic zero and let $$R = A[X_1,\ldots , X_m]$$ . Consider R as standard graded with $$\deg 0$$ X_i 1$$ for all i. In this paper we present comprehensive study components local cohomology s $$H^i_I(R)$$ where I is an arbitrary homogeneous ideal in R. Our seems to the first regard.

Let $R = bigoplus_{n in mathbb{N}_{0}} R_{n}$ be a standardgraded ring, $M$ be a finitely generated graded $R$-module and $J$be a homogenous ideal of $R$. In this paper we study the gradedstructure of the $i$-th local cohomology module of $M$ defined by apair of ideals $(R_{+},J)$, i.e. $H^{i}_{R_{+},J}(M)$. Moreprecisely, we discuss finiteness property and vanishing of thegraded components $H^...

Let R be a d-dimensional local ring, with maximal ideal m, containing a field and let x1, . . . , xd be a system of parameters for R. If depthR ≥ d − 1 and the local cohomology module H m (R) is finitely generated, then there exists an integer n such that the modules R/(x 1 , . . . , x d ) have the same Betti numbers, for all i ≥ n.

Let $R$ be a commutative Noetherian ring, $fa$ anideal of $R$ and $mathcal{D}(R)$ denote the derived category of$R$-modules. For any homologically bounded complex $X$, we conjecture that$sup {bf L}Lambda^{fa}(X)leq$ mag$_RX$. We prove thisin several cases. This generalize the main result of Hatamkhani and Divaani-Aazar cite{HD} for complexes.

We study a question raised by Eisenbud, Mustaţǎ, and Stillman regarding the injectivity of natural maps from Ext modules to local cohomology modules. We obtain some positive answers to this question which extend earlier results of Lyubeznik. In the process, we also prove a vanishing theorem for local cohomology modules which connects theorems previously known in the case of positive characteris...

This paper contributes to the study of local cohomology and topological, in particular connectedness properties. Let I denote an ideal of a regular local ring (R,m) containing a field. There is a description of the Lyubeznik number λd,d(R/I), d = dimR/I, in terms of the topology of V (IR̂). In particular, λd,d(R/I) = 1 if and only if V (IR̂) is connected in codimension one. This provides an alter...

Let a denote an ideal of a local ring (R, m). Let M be a finitely generated Rmodule. There is a systematic study of the formal cohomology modules lim ←− H m(M/a M), i ∈ Z. We analyze their R-module structure, the upper and lower vanishing and non-vanishing in terms of intrinsic data of M, and its functorial behavior. These cohomology modules occur in relation to the formal completion of the pun...

The aim of this work is to describe some operations in the category of regular holonomic D-modules with support a normal crossing and variation zero introduced in [2]. These operations will allow us to compute the characteristic cycle of the local cohomology supported on homogeneous prime ideals of these modules. In particular, we will be able to describe their Bass and dual Bass numbers.