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相关论文: On Eta-Einstein Sasakian Geometry

200 篇论文

In this paper, we give explicit formulae of the Burns-Epstein invariant and global CR invariants via renormalized characteristic forms introduced by Marugame for Sasakian $\eta$-Einstein manifolds. As an application, we show that the latter…

微分几何 · 数学 2025-02-17 Yuya Takeuchi

In this article, we consider Einstein-type manifolds with boundary which generalizes important geometric equations, like static vacuum and static perfect fluid. We investigate some geometric inequalities for those manifolds. Then, we…

微分几何 · 数学 2025-01-24 Maria Andrade

We show that #8(S^2 times S^3) admits two 8-dimensional complex families of inequivalent non-regular Sasakian-Einstein structures. These are the first known non-regular Sasakian-Einstein metrics on this 5-manifold.

微分几何 · 数学 2007-05-23 Charles P. Boyer , Krzysztof Galicki

In the present work we provide a constructive method to describe contact structures on compact homogeneous contact manifolds. The main feature of our approach is to describe the Cartan-Ehresmann connection (gauge field) for principal circle…

微分几何 · 数学 2019-08-07 Eder M. Correa

This is a collection of notes on the properties of left-invariant metrics on the eight-dimensional compact Lie group SU(3). Among other topics we investigate the existence of invariant pseudo-Riemannian Einstein metrics on this manifold. We…

微分几何 · 数学 2021-07-27 Robert Coquereaux

We analyse in a systematic way the (non-)compact four dimensional Einstein-Weyl spaces equipped with a Bianchi metric. We show that Einstein-Weyl structures with a Class A Bianchi metric have a conformal scalar curvature of constant sign on…

广义相对论与量子宇宙学 · 物理学 2009-10-31 Guy Bonneau

We study two natural problems concerning the scalar and the Ricci curvatures of the Bismut connection. Firstly, we study an analog of the Yamabe problem for Hermitian manifolds related to the Bismut scalar curvature, proving that, fixed a…

微分几何 · 数学 2022-12-13 Giuseppe Barbaro

For almost contact metric or almost paracontact metric manifolds there is natural notion of $\eta$-normality. Manifold is called $\eta$-normal if is normal along kernel distribution of characteristic form. In the paper it is proved that…

微分几何 · 数学 2020-11-09 Piotr Dacko

In this paper we introduce the notion of Einstein-type structure on a Riemannian manifold $\varrg$, unifying various particular cases recently studied in the literature, such as gradient Ricci solitons, Yamabe solitons and quasi-Einstein…

微分几何 · 数学 2017-04-25 Giovanni Catino , Paolo Mastrolia , Dario Monticelli , Marco Rigoli

The Newman-Penrose-Perjes formalism is applied to Sasakian 3-manifolds and the local form of the metric and contact structure is presented. The local moduli space can be parameterised by a single function of two variables and it is shown…

微分几何 · 数学 2021-11-15 Brendan S. Guilfoyle

We study Einstein metrics on smooth compact 4-manifolds with an edge-cone singularity of specified cone angle along an embedded 2-manifold. To do so, we first derive modified versions of the Gauss-Bonnet and signature theorems for arbitrary…

微分几何 · 数学 2017-05-17 Michael Atiyah , Claude LeBrun

We define a contact metric structure on the manifold corresponding to a second order ordinary differential equation $d^2y/dx^2=f(x,y,y')$ and show that the contact metric structure is Sasakian if and only if the 1-form $\frac{1}{2}(dp-fdx)$…

微分几何 · 数学 2021-09-01 Tuna Bayrakdar

In this paper, we study several types of geometric problems related to the Ricci curvature on noncompact complex manifolds, such as the existence of K\"{a}hler-Einstein metrics on complete K\"{a}hler manifolds with negative Ricci curvature,…

微分几何 · 数学 2026-04-22 Hanzhang Yin

The object of the present paper is to study some properties of Kenmotsu manifold whose metric is conformal $\eta$-Einstein soliton. We have studied some certain properties of Kenmotsu manifold admitting conformal $\eta$-Einstein soliton. We…

微分几何 · 数学 2021-06-09 Soumendu Roy , Santu Dey , Arindam Bhattacharyya

We prove the existence of extremal Sasakian structures occurring on a countably infinite number of distinct contact structures on $T^2\times S^3$ and certain related manifolds. These structures occur in bouquets and exhaust the Sasaki cones…

微分几何 · 数学 2019-02-20 Charles P. Boyer , Christina W. Tønnesen-Friedman

We show that the Einstein-Hilbert functional, as a functional on the space of Reeb vector fields, detects the vanishing Sasaki-Futaki invariant. In particular, this provides an obstruction to the existence of a constant scalar curvature…

In this paper, we obtain new non-singular Einstein-Sasaki spaces in dimensions D\ge 7. The local construction involves taking a circle bundle over a (D-1)-dimensional Einstein-Kahler metric that is itself constructed as a complex line…

高能物理 - 理论 · 物理学 2009-10-07 W. Chen , H. Lu , C. N. Pope , J. F. Vazquez-Poritz

The object of the present paper is to study some properties of 3-dimensional trans-Sasakian manifold whose metric is {\eta}-Yamabe soliton. We have studied here some certain curvature conditions of 3-dimensional trans-Sasakian manifold…

微分几何 · 数学 2020-11-10 Soumendu Roy , Santu Dey , Arindam Bhattacharyya

We show that there are high-dimensional smooth compact manifolds which admit pairs of Einstein metrics for which the scalar curvatures have opposite signs. These are counter-examples to a conjecture considered by Besse. The proof hinges on…

dg-ga · 数学 2008-02-03 Fabrizio Catanese , Claude LeBrun

We show that by taking a certain scaling limit of a Euclideanised form of the Plebanski-Demianski metrics one obtains a family of local toric Kahler-Einstein metrics. These can be used to construct local Sasaki-Einstein metrics in five…

高能物理 - 理论 · 物理学 2009-11-11 Dario Martelli , James Sparks