Results 131 to 140 of about 12,500,002 (282)

Extensions of Steiner Triple Systems

open access: yesJournal of Combinatorial Designs, Volume 33, Issue 3, Page 94-108, March 2025.
ABSTRACT In this article, we study extensions of Steiner triple systems by means of the associated Steiner loops. We recognize that the set of Veblen points of a Steiner triple system corresponds to the center of the Steiner loop. We investigate extensions of Steiner loops, focusing in particular on the case of Schreier extensions, which provide a ...
Giovanni Falcone   +2 more
wiley   +1 more source

One-dimensional super Calabi-Yau manifolds and their mirrors

open access: yesJournal of High Energy Physics, 2017
We apply a definition of generalised super Calabi-Yau variety (SCY) to supermanifolds of complex dimension one. One of our results is that there are two SCY’s having reduced manifold equal to ℙ 1 $$ {\mathrm{\mathbb{P}}}^1 $$ , namely the projective ...
S. Noja   +4 more
doaj   +1 more source

Twisted conjugacy in soluble arithmetic groups

open access: yesMathematische Nachrichten, Volume 298, Issue 3, Page 763-793, March 2025.
Abstract Reidemeister numbers of group automorphisms encode the number of twisted conjugacy classes of groups and might yield information about self‐maps of spaces related to the given objects. Here, we address a question posed by Gonçalves and Wong in the mid‐2000s: we construct an infinite series of compact connected solvmanifolds (that are not ...
Paula M. Lins de Araujo   +1 more
wiley   +1 more source

The second bounded cohomology of a group with infinitely many ends [PDF]

open access: yesarXiv, 1995
We study the second bounded cohomology of an amalgamated free product of groups, and an HNN extension of a group. As an application, we have a group with infinitely many ends has infinite dimensional second bounded cohomology.
arxiv  

Continuous Group Cohomology and Ext-Groups

open access: yes, 2021
We prove that the continuous group cohomology groups of a locally profinite group $ G $ with coefficients in a smooth $ k $-representation $ $ of $ G $ are isomorphic to the $ \mathrm{Ext}$-groups $ \mathrm{Ext}^i_G(\mathbb{1}, ) $ computed in the category of smooth $ k $-representations of $ G $.
openaire   +4 more sources

A Spectral Sequence Connecting Continuous With Locally Continuous Group Cohomology [PDF]

open access: yesarXiv, 2011
We present a spectral sequence connecting the continuous and 'locally continuous' group cohomologies for topological groups. As an application it is shown that for contractible topological groups these cohomology concepts coincide. Similar results for k-groups and smooth cochains on Lie groups are also obtained.
arxiv  

On the Integral Cohomology of Bianchi Groups [PDF]

open access: yesExperimental Mathematics, 2011
Extensive and systematic machine computations are carried out to investigate the integral cohomology of the Euclidean Bianchi groups and their congruence subgroups. The collected data give insight on several aspects, including the asymptotic behaviour of the torsion in the first homology.
openaire   +4 more sources

Hodge numbers and invariant complex structures of compact nilmanifolds

open access: yesComplex Manifolds, 2016
In this paper, we consider several invariant complex structures on a compact real nilmanifold, and we study relations between invariant complex structures and Hodge numbers.
Yamada Takumi
doaj   +1 more source

Duality of Hodge numbers of compact complex nilmanifolds

open access: yesComplex Manifolds, 2015
A compact K¨ahlerian manifoldM of dimension n satisfies hp,q(M) = hq,p(M) for each p, q.However, a compact complex manifold does not satisfy the equations in general. In this paper, we consider duality of Hodge numbers of compact complex nilmanifolds.
Yamada Takumi
doaj   +1 more source

Symmetric cohomology of groups as a Mackey functor [PDF]

open access: yesarXiv, 2014
Symmetric cohomology of groups, defined by M. Staic in [2], is similar to the way one defines the cyclic cohomology for algebras. We show that there is a well-defined restriction, conjugation and transfer map in symmetric cohomology, which form a Mackey functor under a restriction. Some new properties for the symmetric cohomology group using normalized
arxiv  

Home - About - Disclaimer - Privacy