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Related papers: Approximation of Regular Sasakian Manifolds

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In this paper the notion of quasi-isometry between two Riemannian manifolds has been introduced. This idea is also imposed to study quasi-isometry between two almost contact metric manifolds. Moving further, some curvature properties of two…

Differential Geometry · Mathematics 2025-11-03 Arindam Bhattacharyya , Dipen Ganguly , Paritosh Ghosh , Sumanjit Sarkar

The question of whether a Sasakian metric can admit an additional compatible (K-)contact structure is addressed. In the complete case if the second structure is also assumed Sasakian, works of Tachibana-Yu and Tanno show that the manifold…

Differential Geometry · Mathematics 2013-01-01 Tedi Draghici , Philippe Rukimbira

In this article we study a class of normal{\theta}complex{\theta}contact{\theta}metric{\theta}manifold which is called a complex Sasakian manifold. This kind of manifold has a globally defined complex contact form and normal complex contact…

Differential Geometry · Mathematics 2021-01-05 Aysel Turgut Vanli , İnan Ünal , Keziban Avcu

We show that, for a closed orientable n-manifold, with n not congruent to 3 modulo 4, the existence of a CR-regular embedding into complex (n-1)-space ensures the existence of a totally real embedding into complex n-space. This implies that…

Geometric Topology · Mathematics 2019-09-27 Naohiko Kasuya , Masamichi Takase

We investigate new Clairaut conditions for anti-invariant submersions from normal almost contact metric manifolds onto Riemannian manifolds. We prove that there is no Clairaut anti-invariant submersion admitting vertical Reeb vector field…

Differential Geometry · Mathematics 2017-04-03 Hakan Mete Taştan , Sibel Gerdan

Let U be a real form of a complex semisimple Lie group, and tau, sigma, a pair of commuting involutions on U. This data corresponds to a reflective submanifold of a symmetric space, U/K. We define an associated integrable system, and…

Differential Geometry · Mathematics 2007-10-06 David Brander

This is the very first paper to focus on the CR analogue of Yau's uniformization conjecture in a complete noncompact pseudohermitian $(2n+1)$-manifold of vanishing torsion (i.e. Sasakian manifold) which is an odd dimensional counterpart of…

Differential Geometry · Mathematics 2018-04-18 Shu-Cheng Chang , Yingbo Han , Chien Lin

In this paper we demonstrate the existence of Sasakian-Einstein structures on certain 2-connected rational homology 7-spheres. These appear to be the first non-regular examples of Sasakian-Einstein metrics on simply connected rational…

Differential Geometry · Mathematics 2007-05-23 Charles P. Boyer , Krzysztof Galicki , Michael Nakamaye

We study the geometry of almost contact pseudo-metric manifolds in terms of tensor fields $h:=\frac{1}{2}\pounds _\xi \varphi$ and $\ell := R(\cdot,\xi)\xi$, emphasizing analogies and differences with respect to the contact metric case.…

Differential Geometry · Mathematics 2018-06-01 Venkatesha , Devaraja Mallesha Naik , Mukut Mani Tripathi

Let $X$ be a compact real algebraic set of dimension $n$. We prove that every Euclidean continuous map from $X$ into the unit $n$-sphere can be approximated by regulous map. This strengthens and generalizes previously known results.

Algebraic Geometry · Mathematics 2017-06-16 Maciej Zieliński

In this paper we study the 3-dimensional $(\varepsilon) $-para Sasakian manifolds. We obtain an necessary and sufficient condition for an $(\varepsilon ) $-para Sasakian 3 -manifold to be an indefinite space form. We show that a…

Differential Geometry · Mathematics 2016-08-14 Selcen Yüksel Perktaş , Erol Kılıç , Mukut Mani Tripathi , Sadık Keleş

We carry on a systematic study of nearly Sasakian manifolds. We prove that any nearly Sasakian manifold admits two types of integrable distributions with totally geodesic leaves which are, respectively, Sasakian or $5$-dimensional nearly…

Differential Geometry · Mathematics 2022-06-16 Beniamino Cappelletti-Montano , Giulia Dileo

In this paper, we show that the uniform L^{4}-bound of the transverse Ricci curvature along the Sasaki-Ricci flow on a compact quasi-regular Sasakian (2n+1)-manifold M of general type. As an application, any solution of the normalized…

Differential Geometry · Mathematics 2022-03-02 Shu-Cheng Chang , Yingbo Han , Chien Lin , Chin-Tung Wu

Extending the work of G. Sz\'ekelyhidi and T. Br\"onnle to Sasakian manifolds we prove that a small deformation of the complex structure of the cone of a constant scalar curvature Sasakian manifold admits a constant scalar curvature…

Differential Geometry · Mathematics 2015-12-01 Carl Tipler , Craig van Coevering

We propose a new approach to the existence of constant transversal scalar curvature Sasaki structures drawing on ideas and tools from the CR Yamabe problem, establishing a link between the CR Yamabe invariant, the existence of Sasaki…

Differential Geometry · Mathematics 2025-09-03 Abdellah Lahdili , Eveline Legendre , Carlo Scarpa

We investigate the topology of the compact submanifolds in round spheres that satisfy a lower bound on the Ricci curvature depending only on the length of the mean curvature vector of the immersion. Just in special cases, the limited…

Differential Geometry · Mathematics 2025-09-03 Marcos Dajczer , Theodoros Vlachos

A fundamental result in global analysis and nonlinear elasticity asserts that given a solution $\mathfrak{S}$ to the Gauss--Codazzi--Ricci equations over a simply-connected closed manifold $(\mathcal{M}^n,g)$, one may find an isometric…

Differential Geometry · Mathematics 2026-01-30 Siran Li , Xiangxiang Su

We define the notion of normal A-schemes, and approximable A-schemes. Approximable A-schemes inherit many good properties of ordinary schemes. As a consequence, we see that the Zariski-Riemann space can be regarded in two ways -- either as…

Algebraic Geometry · Mathematics 2011-10-07 Satoshi Takagi

We show the regularity of, and derive a-priori estimates for (weakly) harmonic maps from a Riemannian manifold into a Euclidean sphere under the assumption that the image avoids some neighborhood of a half-equator. The proofs combine…

Differential Geometry · Mathematics 2009-12-03 Juergen Jost , Yuanlong Xin , Ling Yang

In this paper, we concern with the Sasaki analogue of Yau uniformization conjecture in a complete noncompact Sasakian manifold with nonnegative transverse bisectional curvature. As a consequence, we confirm that any $5$-dimensional complete…

Differential Geometry · Mathematics 2026-01-16 Shu-Cheng Chang , Yingbo Han , Chien Lin , Chin-Tung Wu