Results 21 to 30 of about 4,505 (170)
DERIVED HECKE ALGEBRA AND COHOMOLOGY OF ARITHMETIC GROUPS
Forum of Mathematics, Pi, 2019 We describe a graded extension of the usual Hecke algebra: it acts in a graded fashion on the cohomology of an arithmetic group $\unicode[STIX]{x1D6E4}$.
AKSHAY VENKATESH
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The triviality of dihedral cohomology for operator algebras
Scientific AfricanThis article delves into algebraic topology, specifically (co)homology theory, which is essential in various mathematical fields. It explores different types of (co)homology groups such as Hochschild, cyclic, reflexive, and dihedral, focusing on dihedral
Samar A.A. Quota +3 more
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On bounded cohomology of amalgamated products of groups
International Journal of Mathematics and Mathematical Sciences, 2004 We investigate the structure of the singular part of the second bounded cohomology group of amalgamated products of groups by constructing an analog of the initial segment of the Mayer-Vietoris exact cohomology sequence for the spaces of pseudocharacters.
Igor V. Erovenko
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The Serre duality theorem for Reimann surfaces
International Journal of Mathematics and Mathematical Sciences, 1984 Given a Riemann surface S, there exists a finitely generated Fuchsian group G of the first kind acting on the upper half plane U, such that S≅U/G. This isomorphism makes it possible to use Fuchsian group methods to prove theorems about Riemann surfaces ...
Ranjan Roy
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On algebraic characterizations for finiteness of the dimension of EG [PDF]
Iranian Journal of Numerical Analysis and Optimization, 2008 Certain algebraic invariants of the integral group ring ZG of a group G were introduced and investigated in relation to the problem of extending the Farrell-Tate cohomology, which is defined for the class of groups of finite virtual cohomological ...
Olympia Talelli
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Co-prolongations of a group extension [PDF]
International Journal of Group Theory, 2014 The aim of this paper is to study co-prolongationsof central extensions. We construct the obstruction theory forco-prolongations and classify the equivalence classes of these by kernels of ahomomorphisms between 2-dimensional cohomology groups of groups.
Nguyen Thi Thu Thuy +2 more
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Substitutions with Vanishing Rotationally Invariant First Cohomology
Discrete Dynamics in Nature and Society, 2012 The cohomology groups of tiling spaces with three-fold and nine-fold symmetries are obtained. The substitution tilings are characterized by the fact that they have vanishing first cohomology group in the space of tilings modulo a rotation.
Juan García Escudero
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HILBERT STRATIFOLDS AND A QUILLEN TYPE GEOMETRIC DESCRIPTION OF COHOMOLOGY FOR HILBERT MANIFOLDS
Forum of Mathematics, Sigma, 2018 In this paper we use tools from differential topology to give a geometric description of cohomology for Hilbert manifolds. Our model is Quillen’s geometric description of cobordism groups for finite-dimensional smooth manifolds [Quillen, ‘Elementary ...
MATTHIAS KRECK, HAGGAI TENE
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First and second cohomology group of a bu ndle
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2012 Let (E, π, M) be a vector bundle. We define two cohomology groups associated to π using the first and second order jet manifolds of this bundle. We prove that one of them is isomorphic with a Čech cohomology group of the base space.
Manea Adelina
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International Journal of Mathematics and Mathematical Sciences, 2006 We discuss the calculation of integral cohomology ring of LG/T and ΩG. First we describe the root system and Weyl group of LG, then we give some homotopy equivalences on the loop groups and homogeneous spaces, and calculate the cohomology ring structures
Cenap Özel, Erol Yilmaz
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