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Related papers: A step towards the Alekseevskii Conjecture

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This article generalises to K\"ahler orbifolds general results on uniformisation of compact K\"ahler manifolds such as the Shafarevich conjecture for linear fundamental groups.

Algebraic Geometry · Mathematics 2013-02-21 Philippe Eyssidieux

In this short note, we show that homogeneous Ricci solitons are algebraic. As an application, we see that the generalized Alekseevskii conjecture is equivalent to the Alekseevskii conjecture.

Differential Geometry · Mathematics 2014-11-11 Michael Jablonski

This paper initiates the study of the Einstein equation on homogeneous supermanifolds. First, we produce explicit curvature formulas for graded Riemannian metrics on these spaces. Next, we present a construction of homogeneous…

Mathematical Physics · Physics 2026-04-01 Yang Zhang , Mark D. Gould , Artem Pulemotov , Jorgen Rasmussen

In this note, we show that a nontrivial, compact, degenerate or nondegenerate, gradient Einstein-type manifold of constant scalar curvature is isometric to the standard sphere with a well defined potential function. Moreover, under some…

Differential Geometry · Mathematics 2021-05-04 José Nazareno Vieira Gomes

We give necessary conditions for the existence of a compact manifold locally modelled on a given homogeneous space, which generalize some earlier results, in terms of relative Lie algebra cohomology. Applications include both reductive and…

Differential Geometry · Mathematics 2017-05-09 Yosuke Morita

We present a classification, up to isomorphisms, of all the homogeneous spaces of the Lorentz group with dimension lower than six. At the same time, we classify, up to conjugation, all the non-discrete closed subgroup of the Lorentz group…

Mathematical Physics · Physics 2007-05-23 M. Toller

We present simple examples of finite-dimensional connected homogeneous spaces (they are actually topological manifolds) with nonhomogeneous and nonrigid factors. In particular, we give an elementary solution of an old problem in general…

Geometric Topology · Mathematics 2012-03-21 M. Cárdenas , F. F. Lasheras , A. Quintero , D. Repovš

We give an elementary proof of a compact embedding theorem in abstract Sobolev spaces. The result is first presented in a general context and later specialized to the case of degenerate Sobolev spaces defined with respect to nonnegative…

Analysis of PDEs · Mathematics 2011-11-01 Seng-Kee Chua , Scott Rodney , Richard L. Wheeden

In this paper, we prove a generalized Donaldson-Uhlenbeck-Yau theorem on Higgs bundles over a class of non-compact Gauduchon manifolds.

Differential Geometry · Mathematics 2018-04-25 Chuanjing Zhang , Pan Zhang , Xi Zhang

We construct examples of compact homogeneous Riemannian manifolds admitting an invariant Bismut connection that is Ricci flat and non-flat, proving in this way that the generalized Alekseevsky-Kimelfeld theorem does not hold. The…

Differential Geometry · Mathematics 2025-01-03 Fabio Podestà , Alberto Raffero

We establish a relative version of the abstract "affine representability" theorem in ${\mathbb A}^1$--homotopy theory from Part I of this paper. We then prove some ${\mathbb A}^1$--invariance statements for generically trivial torsors under…

Algebraic Geometry · Mathematics 2018-03-16 Aravind Asok , Marc Hoyois , Matthias Wendt

We develop a general method to calculate entropy numbers of standard Sobolev's classes on an arbitrary compact homogeneous Riemannian manifold. Our method is essentially based on a detailed study of geometric characteristics of norms…

Functional Analysis · Mathematics 2015-04-27 A. Kushpel , J. Levesley

We construct the homogeneous Einstein equation for generalized flag manifolds $G/K$ of a compact simple Lie group $G$ whose isotropy representation decomposes into five inequivalent irreducible $\Ad(K)$-submodules. To this end we apply a…

Differential Geometry · Mathematics 2019-11-25 Andreas Arvanitoyeorgos , Ioannis Chrysikos , Yusuke Sakane

The Hodge decomposition is well-known for compact manifolds. The result has been extended by Kodaira to include non-compact manifolds and $L^2$ forms. We further extend the Hodge decomposition to the Sobolev space $H^1$ for general…

Differential Geometry · Mathematics 2019-01-01 Chi Hin Chan , Magdalena Czubak , Carlos Pinilla Suarez

Let $M = G/H$ be a connected simply connected homogeneous manifold of a compact, not necessarily connected Lie group $G$. We will assume that the isotropy $H$-module $\mathfrak {g/h}$ has a simple spectrum, i.e. irreducible submodules are…

Differential Geometry · Mathematics 2013-05-17 Michail M. Graev

The classification of homogeneous quaternionic manifolds has been done by Alekseevskii, Wolf et al using transitive solvable group of isometries. These manifolds are not generically symmetric, but there is a subset of quaternionic manifolds…

High Energy Physics - Theory · Physics 2008-11-26 Keshav Dasgupta , Veronique Hussin , Alisha Wissanji

We obtain a structure theorem for closed, cohomogeneity one Alexandrov spaces and we classify closed, cohomogeneity one Alexandrov spaces in dimensions 3 and 4. As a corollary, we obtain the classification of closed, $n$-dimensional,…

Differential Geometry · Mathematics 2010-09-21 Fernando Galaz-Garcia , Catherine Searle

The main result of this article provides a characterization of reductive homogeneous spaces equipped with some geometric structure (non necessarily pseudo-Riemannian) in terms of the existence of certain connection. The result generalizes…

Differential Geometry · Mathematics 2021-08-20 J. L. Carmona Jimenez , M. Castrillon Lopez

Among plenty of applications, low-dimensional homogeneous spaces appear in cosmological models as both, classical factor spaces of multidimensional geometry and minisuperspaces in canonical quantization. Here a new tool to restrict their…

General Relativity and Quantum Cosmology · Physics 2016-08-31 M. Rainer

The methods of Information geometry have been glowing up to develop various subjects of theoretical physics, including quantum information systems. The present article has two purposes. The first one is to develop general theory of…

Differential Geometry · Mathematics 2024-08-06 Jun-ichi Inoguchi , Yu Ohno