Results 161 to 170 of about 1,003,210 (193)

The Cohomological Dimension of a Directed Set

Canadian Journal of Mathematics, 1973
Let R be a ring with identity, and let C be a small, nonempty category. We denote the category of right R-modules by AbR and the category of contravariant functors C → AbR by AbRC*. The limit functoris left exact, and its kth right derived functor is denoted by colimk.
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Cohomological Dimension of Algebraic Varieties

The Annals of Mathematics, 1968
Let X be a scheme of finite type over a field k. The cohomological dimension of X is the smallest integer n > 0 such that H'(X, F) = 0 for all i > n, and for all quasi-coherent sheaves F on X. There are two well-known theorems about the cohomological dimension of X.
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A bound for the Bredon cohomological dimension

Journal of Group Theory, 2007
Summary: We prove that if \(G\) is a group with a bound on the lengths of finite subgroups and \(G\) has finite Bredon cohomological dimension, then this dimension is bounded by the sum of the previous bound and the projective dimension of a certain \(\mathbb{Z} G\)-module.
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Periodic cohomology and subgroups with bounded Bredon cohomological dimension

Mathematical Proceedings of the Cambridge Philosophical Society, 2008
AbstractMislin and Talelli showed that a torsion-free group in$\HF$with periodic cohomology after some steps has finite cohomological dimension. In this note we look at similar questions for groups with torsion by considering Bredon cohomology. In particular we show that every elementary amenable group acting freely and properly on some$\R^n$×Smadmits ...
Jo, Jang Hyun, Nucinkis, Brita E.A.
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Cohomological dimension with respect to perfect groups [PDF]

Topology and Its Applications, 1996
We introduce new classes of compact metric spaces: Cannon—Štan'ko, Cainian, and nonabelian compacta. In particular, we investigate compacta of cohomological dimension one with respect to certain classes of nonabelian groups, e.g., perfect groups. We also
Dusan D Repovš, Alexander N Dranishnikov   +1 more
exaly   +2 more sources

Cohomology with support of dimension ≤ d

Journal of Algebra and Its Applications, 2016
Let [Formula: see text] be a commutative Noetherian ring, [Formula: see text] be an integer and let [Formula: see text] denote the ideals of [Formula: see text] of dimension [Formula: see text]. For an integer [Formula: see text] and [Formula: see text]-modules [Formula: see text], we define the [Formula: see text]th cohomology module [Formula: see ...
Zamani, N., Bijan-Zadeh, M. H., Sayedsadeghi, M. S.   +2 more
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Yang–Mills cohomology in four dimensions

Journal of Mathematical Physics, 1986
The local polynomial cohomology space of the Yang–Mills BRS operator in four dimensions is computed. In order to simplify the analysis, without omitting the physically interesting cases, the investigation is limited to polynomials whose Fadeev–Popov charge and UV naive dimensions have upper bounds.
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On cohomological dimension of homomorphisms

Proceedings of the American Mathematical Society
The (co)homological dimension of a homomorphism ϕ : G
De Saha, Aditya, Dranishnikov, Alexander
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The Cohomological Dimension of Gs

2002
In this chapter k is an arbitrary global field of finite type. We study the cohomology groups H v (Gs) in more detail and prove in particular that H3(Gs) vanishes under certain conditions.
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Cohomological Dimension

2000
Luis Ribes, Pavel Zalesskii
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