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Related papers: The $G_2$ geometry of $3$-Sasaki structures

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We obtain new examples of non-symmetric Einstein solvmanifolds by combining two techniques. In \cite{T2}, H. Tamaru constructs new {\em attached} solvmanifolds, which are submanifolds of the solvmanifolds corresponding to noncompact…

Differential Geometry · Mathematics 2014-01-03 Megan M. Kerr

We study existence of invariant Einstein metrics on complex Stiefel manifolds $G/K = \SU(\ell+m+n)/\SU(n) $ and the special unitary groups $G = \SU(\ell+m+n)$. We decompose the Lie algebra $\frak g$ of $G$ and the tangent space $\frak p$ of…

Differential Geometry · Mathematics 2020-06-30 Andreas Arvanitoyeorgos , Yusuke Sakane , Marina Statha

We formulate an approach to the geometry of Riemann-Cartan spaces provided with nonholonomic distributions defined by generic off-diagonal and nonsymmetric metrics inducing effective nonlinear and affine connections. Such geometries can be…

General Relativity and Quantum Cosmology · Physics 2008-12-19 Sergiu I. Vacaru

We consider the problem of finding complete conformal metrics with prescribed curvature functions of the Einstein tensor and of more general modified Schouten tensors. To achieve this, we reveal an algebraic structure of a wide class of…

Differential Geometry · Mathematics 2021-05-04 Rirong Yuan

We consider hypersurfaces in Einstein-Sasaki 5-manifolds which are tangent to the characteristic vector field. We introduce evolution equations that can be used to reconstruct the 5-dimensional metric from such a hypersurface, analogous to…

Differential Geometry · Mathematics 2008-11-26 Diego Conti

We introduce and study a notion of `Sasaki with torsion structure' (ST) as an odd-dimensional analogue of K\"ahler with torsion geometry (KT). These are normal almost contact metric manifolds that admit a unique compatible connection with…

Differential Geometry · Mathematics 2014-07-30 Diego Conti , Thomas Bruun Madsen

Starting with a compact hyperbolic cone-manifold of dimension greater than or equal to 3, we study the deformations of the metric with the aim of getting Einstein cone-manifolds. If the singular locus is a closed codimension 2 submanifold…

Differential Geometry · Mathematics 2016-08-16 Grégoire Montcouquiol

Generalized symmetries of the Einstein equations are infinitesimal transformations of the spacetime metric that formally map solutions of the Einstein equations to other solutions. The infinitesimal generators of these symmetries are…

General Relativity and Quantum Cosmology · Physics 2009-10-22 C. G. Torre , I. M. Anderson

We overview the properties of non-infinitesimal deformations of G2-structures on seven-manifolds, and in particular, focus on deformations that lie in the seven-dimensional representation of G2 and are thus defined by a vector. We then…

Differential Geometry · Mathematics 2013-01-22 Sergey Grigorian

We classify all self-dual Einstein four-manifolds invariant under a principal action of the three-dimensional Heisenberg group with non-degenerate orbits. The metrics are explicit and we find, in particular, that the Einstein constant can…

Differential Geometry · Mathematics 2022-11-23 Vicente Cortés , Ángel Murcia

It is well known that the Einstein equation on a Riemannian flag manifold $(G/K,g)$ reduces to an algebraic system if $g$ is a $G$-invariant metric. In this paper we obtain explicitly new invariant Einstein metrics on generalized flag…

Differential Geometry · Mathematics 2016-06-09 Luciana Aparecida Alves , Neiton Pereira da Silva

In this work we are interested in studying deformations of the $\sigma_2$-curvature and the volume. For closed manifolds, we relate critical points of the total $\sigma_2$-curvature functional to the $\sigma_2$-Einstein metrics and, as a…

Differential Geometry · Mathematics 2022-07-05 Maria Andrade , Tiarlos Cruz , Almir Silva Santos

We present new exact solutions for two-dimensional geometries generated by continuous distributions of topological defects within a conformal metric framework. By reformulating Einstein's equations in two dimensions as a Poisson equation…

General Relativity and Quantum Cosmology · Physics 2025-07-09 A. M. de M. Carvalho , G. Q. Garcia , C. Furtado

We consider some infinitesmal and global deformations of G_2 structures on 7-manifolds. We discover a canonical way to deform a G_2 structure by a vector field in which the associated metric gets "twisted" in some way by the vector cross…

Differential Geometry · Mathematics 2019-05-16 Spiro Karigiannis

In this paper we show how Einstein metrics are naturally described using the quantization of the algebra of functions on a Kahler manifold M. In this setup one interprets M as the phase space itself, equipped with the Poisson brackets…

High Energy Physics - Theory · Physics 2010-09-30 Sergio Lukic

For any $G$-invariant metric on a compact homogeneous space $M=G/K$, we give a formula for the Lichnerowicz Laplacian restricted to the space of all $G$-invariant symmetric $2$-tensors in terms of the structural constants of $G/K$. As an…

Differential Geometry · Mathematics 2022-07-01 Jorge Lauret , Cynthia E. Will

The Iwasawa manifold is uplifted to seven-folds of either G_2 holonomy or SU(3) structure, explicit new metrics for the same having been constructed in this work. We uplift the Iwasawa manifold to a G_2 manifold through "size" deformation…

High Energy Physics - Theory · Physics 2009-11-11 Anne Franzen , Payal Kaura , Aalok Misra , Rajyavardhan Ray

The author has elsewhere given a complete classification of those compact oriented Einstein 4-manifolds on which the self-dual Weyl curvature is everywhere positive in the direction of some self-dual harmonic 2-form. In this article,…

Differential Geometry · Mathematics 2019-03-26 Claude LeBrun

In this paper, we introduce the notion of standard homogeneous $(\alpha_1,\alpha_2)$-metrics, as a natural non-Riemannian deformation for the normal homogeneous Riemannian metrics. We prove that with respect to the given bi-invariant inner…

Differential Geometry · Mathematics 2019-12-03 Lei Zhang , Ming Xu

In [11] it was proved that, given a compact toric Sasaki manifold of positive basic first Chern class and trivial first Chern class of the contact bundle, one can find a deformed Sasaki structure on which a Sasaki-Einstein metric exists. In…

Differential Geometry · Mathematics 2008-11-26 Koji Cho , Akito Futaki , Hajime Ono