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Related papers: A criterion for cohomological dimension

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We study a notion of dimension which was introduced by R. Heitmann in his remarkable paper in 1984, and also a related notion, implicit in the proofs in his paper. We develop these notions in the general framework of distributive lattices…

Commutative Algebra · Mathematics 2022-01-19 Thierry Coquand , Henri Lombardi , Claude Quitté

Jacobson developed a counterpart of Galois theory for purely inseparable field extensions in positive characteristic. In his theory, a certain type of derivations replace the role of the generators of Galois groups. This article provides a…

Algebraic Geometry · Mathematics 2024-09-06 Kentaro Mitsui , Nobuo Sato

We prove that two arithmetically significant extensions of a field F coincide if and only if the Witt ring WF is a group ring Z/n[G]. Furthermore, working modulo squares with Galois groups which are 2-groups, we establish a theorem…

Algebraic Topology · Mathematics 2007-05-23 Alejandro Adem , Wenfeng Gao , Dikran Karagueuzian , Jan Minac

We establish cohomological and extension dimension versions of the Hurewicz dimension-raising theorem

Geometric Topology · Mathematics 2007-05-23 Gencho Skordev , Vesko Valov

We study partial homology and cohomology from ring theoretic point of view via the partial group algebra $\mathbb{K}_{par}G$. In particular, we link the partial homology and cohomology of a group $G$ with coefficients in an irreducible…

Group Theory · Mathematics 2023-11-10 Marcelo Muniz Alves , Mikhailo Dokuchaev , Dessislava H. Kochloukova

We prove that the $k$th term of the Johnson filtration of a closed, orientable surface of genus $g \geq 2$ has cohomological dimension $2g - 3$ for all $k \geq 3$ and $g \geq 2$. This answers a question of Farb and Bestvina--Bux--Margalit.

Geometric Topology · Mathematics 2023-11-21 Daniel Minahan

Billey and Braden defined a geometric pattern map on flag manifolds which extends the generalized pattern map of Billey and Postnikov on Weyl groups. The interaction of this torus equivariant map with the Bruhat order and its action on line…

Algebraic Geometry · Mathematics 2016-03-15 Praise Adeyemo , Frank Sottile

We prove the "divisible case" of the Milnor-Bloch-Kato conjecture (which is the first step of Voevodsky's proof of this conjecture for arbitrary prime l) in a rather clear and elementary way. Assuming this conjecture, we construct a 6-term…

K-Theory and Homology · Mathematics 2014-05-08 Leonid Positselski

We make further observations on the features of Galois cohomology in the general model theoretic context. We make explicit the connection between forms of definable groups and first cohomology sets with coefficients in a suitable…

Logic · Mathematics 2021-05-28 Omar Leon Sanchez , David Meretzky , Anand Pillay

We prove two homotopy decomposition theorems for the loops on co-H-spaces, including a generalization of the Hilton-Milnor Theorem. These are applied to problems arising in algebra, representation theory, toric topology, and the study of…

Algebraic Topology · Mathematics 2010-11-08 Jelena Grbic , Stephen Theriault , Jie Wu

We show a quantum version of Chern character homomorphism from the small quantum K-theory to the small quantum cohomology in the cases of projective spaces and incidence varieties, whose classical limit gives the classical Chern character…

Algebraic Geometry · Mathematics 2025-07-17 Hua-Zhong Ke , Changzheng Li , Jiayu Song

We advance the understanding of K-theory of quadratic forms by computing the slices of the motivic spectra representing hermitian K-groups and Witt-groups. By an explicit computation of the slice spectral sequence for higher Witt-theory, we…

K-Theory and Homology · Mathematics 2017-05-31 Oliver Röndigs , Paul Arne Østvær

This paper studies Moore's measurable cohomology theory for locally compact groups and Polish modules. An elementary dimension-shifting argument is used to show that all classes in that theory have representatives with considerable extra…

Group Theory · Mathematics 2012-06-14 Tim Austin

Let p be a prime and F a field containing a primitive pth root of unity. Then for n in N, the cohomological dimension of the maximal pro-p-quotient G of the absolute Galois group of F is <=n if and only if the corestriction maps H^n(H,Fp)…

Number Theory · Mathematics 2008-06-26 John Labute , Nicole Lemire , Jan Minac , John Swallow

A field $K$ is $d$-local if there exist fields $K=k_d,...,k_0$ with $k_{i+1}$ complete discrete valuation with residue field $k_i$, and $k_0$ finite of characteristic $p$. By work of Deninger and Wingberg, the Galois cohomology of such…

Number Theory · Mathematics 2026-03-16 Antoine Galet

If the $\ell$-adic cohomology of a projective smooth variety, defined over a $\frak{p}$-adic field $K$ with finite residue field $k$, is supported in codimension $\ge 1$, then any model over the ring of integers of $K$ has a $k$-rational…

Number Theory · Mathematics 2007-05-23 Hélène Esnault

For schemes X over global or local fields, or over their rings of integers, K. Kato stated several conjectures on certain complexes of Gersten-Bloch-Ogus type, generalizing the fundamental exact sequence of Brauer groups for a global field.…

Algebraic Geometry · Mathematics 2014-12-05 Uwe Jannsen

The paper provides a combinatorial method to decide when the space of local systems with non vanishing first cohomology on the complement to an arrangement of lines in a complex projective plane has as an irreducible component a subgroup of…

Combinatorics · Mathematics 2007-05-23 A. Libgober , S. Yuzvinsky

We generalize some known results on the relation between the cohomological and projective dimension. Then we examine the set-theoretically Cohen-Macaulay ideals to find some cohomological characterization of these kind of ideals.

Commutative Algebra · Mathematics 2021-06-15 Majid Eghbali , Alberto F. Boix

We give a new interpretation of Kozsul cohomology, which is equivalent under the Bridgeland-King-Reid equivalence to Voisin's Hilbert scheme interpretation in dimensions 1 and 2, but is different in higher dimensions. As an application, we…

Algebraic Geometry · Mathematics 2014-07-29 David H Yang