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Related papers: Cocycles for Kottwitz cohomology

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We study the torsion cohomology classes of Shimura varieties of type Kottwitz-Harris-Taylor and we show that " up to an arbitrary place " one can raise them to an automorphic representation. In application, to any mod $l$ system of Hecke…

Number Theory · Mathematics 2016-11-01 Pascal Boyer

Let $G$ be a simple simply connected group scheme defined over ${\mathbb F}_{p}$ and $k$ be an algebraically closed field of characteristic $p>0$. Moreover, let $B$ be a Borel subgroup of $G$ and $U$ be the unipotent radical of $B$. In this…

Group Theory · Mathematics 2014-10-10 Christopher P. Bendel , Daniel K. Nakano , Cornelius Pillen

Zonotopal algebras of vector arrangements are combinatorially-defined algebras with connections to approximation theory, introduced by Holtz and Ron and independently by Ardila and Postnikov. We show that the internal zonotopal algebra of a…

Combinatorics · Mathematics 2025-05-13 Colin Crowley , Galen Dorpalen-Barry , André Henriques , Nicholas Proudfoot

Let $A$ be a C$^*$-algebra, and let $X$ be a Banach $A$-bimodule. B. E. Johnson showed that local derivations from $A$ into $X$ are derivations. We extend this concept of locality to the higher cohomology of a $C^*$-algebra %for…

Operator Algebras · Mathematics 2017-11-21 Ebrahim Samei

I. M. Gelfand and D. B. Fuks have studied the cohomology of the Lie algebra of vector fields on a manifold. In this article, we generalize their main tools to compute the Leibniz cohomology, by extending the two spectral sequences…

K-Theory and Homology · Mathematics 2007-05-23 Alessandra Frabetti , Friedrich Wagemann

Let $X$ be an algebraic scheme over an algebraically closed field and $\ell$ a prime number invertible on $X$. According to classical results (due essentially to A. Grothendieck, M. Artin and P. Deligne), the \'etale cohomology groups…

Algebraic Geometry · Mathematics 2016-01-20 David A. Madore , Fabrice Orgogozo

This is a further investigation of our approach to group actions in homological algebra in the settings of homology of {\Gamma}-simplicial groups, particularly of {\Gamma}-equivariant homology and cohomology of {\Gamma}-groups. This…

K-Theory and Homology · Mathematics 2021-07-26 Hvedri Inassaridze

It known from the work of Feigin-Tsygan, Weibel and Keller that the cohomology groups of a smooth complex variety X can be recovered from (roughly speaking) its derived category of coherent sheaves. In this paper we show that for a finite…

Algebraic Geometry · Mathematics 2007-05-23 Vladimir Baranovsky

A general method for establishing results over a commutative complete intersection local ring by passing to differential graded modules over a graded exterior algebra is described. It is used to deduce, in a uniform way, results on the…

Commutative Algebra · Mathematics 2010-03-30 Luchezar L. Avramov , Srikanth B. Iyengar

We study the local cohomology modules H^i_B(R) for a reduced monomial ideal B in a polynomial ring R=k[X_1,...,X_n]. We consider a grading on R which is coarser than the Z^n-grading such that each component of H^i_B(R) is finite dimensional…

Algebraic Geometry · Mathematics 2007-05-23 David Eisenbud , Mircea Mustata , Mike Stillman

Let $ G $ be a cyclic group, in this paper, we study the Herbrand quotient and $ 1-$th cohomology group on finitely generated $ G-$modules in some cases. When $ G $ is of order $ 2, $ the order of the cohomology group is explicitly related…

Number Theory · Mathematics 2026-04-10 Derong Qiu

In this paper, we study equivariant real cycle class maps for group actions on real schemes, with a view toward Witt-sheaf characteristic classes. The cycle class maps take values in singular cohomology of the real points of the quotient…

Algebraic Topology · Mathematics 2026-02-25 Lorenzo Mantovani , Ákos K. Matszangosz , Matthias Wendt

For a (co)monad T_l on a category M, an object X in M, and a functor \Pi: M \to C, there is a (co)simplex Z^*:=\Pi T_l^{* +1} X in C. Our aim is to find criteria for para-(co)cyclicity of Z^*. Construction is built on a distributive law of…

K-Theory and Homology · Mathematics 2012-01-27 Gabriella Böhm , Dragos Stefan

This paper is our first step in establishing a de Rham model for equivariant twisted $K$-theory using machinery from noncommutative geometry. Let $G$ be a compact Lie group, $M$ a compact manifold on which $G$ acts smoothly. For any $\alpha…

K-Theory and Homology · Mathematics 2015-05-01 Jean-Louis Tu , Ping Xu

Let G be a group and let W be an algebra over a field K. We will say that W is a G-graded twisted algebra if W can be written as a direct sum over the elements of G of one dimensional K-vector spaces. It is also assumed that W has no…

Rings and Algebras · Mathematics 2015-05-18 Juan P. Hernandez , Juan D. Velez , Luis A. Wills-Toro , Edisson Gallego

In this paper, we study the cohomology of semisimple local systems in the spirit of classical Hodge theory. On the one hand, we establish a generalization of Hodge-Riemann bilinear relations. For a semisimple local system on a smooth…

Algebraic Geometry · Mathematics 2024-12-13 Chuanhao Wei , Ruijie Yang

We show that the diagonal complex computing the Gerstenhaber-Schack cohomology of a bialgebra (that is, the cohomology theory governing bialgebra deformations) can be given the structure of an operad with multiplication if the bialgebra is…

K-Theory and Homology · Mathematics 2020-06-16 Domenico Fiorenza , Niels Kowalzig

A well-known and old result of Hazewinkel and Koszul states that the cohomology of a finite-dimensional Lie algebra is isomorphic, up to a suitable shift, to its twisted homology, a Lie-theoretical version of Poincare duality. This paper…

Quantum Algebra · Mathematics 2026-01-26 Andrey Lazarev , Rong Tang

We use Galois group actions on \'etale cohomology to prove results of formality for dg-operads and dg-algebras with torsion coefficients. Our theory applies, among other related constructions, to the dg-operad of singular chains on the…

Algebraic Topology · Mathematics 2025-08-05 Joana Cirici , Geoffroy Horel

If $A$ is a finite-dimensional algebra graded by a group $G$, and $\sigma \in G$, we define a variant of paratrophic matrix associated with $A$ and $\sigma$, and we use it to characterize the $\sigma$-graded Frobenius property for $A$. We…

Rings and Algebras · Mathematics 2025-12-18 Sorin Dascalescu , Constantin Nastasescu , Laura Nastasescu , Paul Rebenciuc