Results 21 to 30 of about 1,987 (109)

C-R Immersions and Sub-Riemannian Geometry

Axioms, 2023
On any strictly pseudoconvex CR manifold M, of CR dimension n, equipped with a positively oriented contact form θ, we consider natural ϵ-contractions, i.e., contractions gϵM of the Levi form Gθ, such that the norm of the Reeb vector field T of (M, θ) is ...
Elisabetta Barletta, Sorin Dragomir, Francesco Esposito   +2 more
doaj   +1 more source

A Lichnerowicz–Obata–Cheng Type Theorem on Finsler Manifolds

Mathematics, 2018
Let ( M , F , d μ ) be a Finsler manifold with the Ricci curvature bounded below by a positive number and constant S-curvature. We prove that, if the first eigenvalue of the Finsler⁻Laplacian attains its lower bound, then M is ...
Songting Yin, Pan Zhang
doaj   +1 more source

On Differential Equations Characterizing Legendrian Submanifolds of Sasakian Space Forms

Mathematics, 2020
In this paper, we give an estimate of the first eigenvalue of the Laplace operator on minimally immersed Legendrian submanifold N n in Sasakian space forms N ˜ 2 n + 1 ( ϵ ) . We prove that a minimal Legendrian submanifolds in
Rifaqat Ali, Fatemah Mofarreh, Nadia Alluhaibi, Akram Ali, Iqbal Ahmad   +4 more
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Almost Ricci–Yamabe soliton on contact metric manifolds [PDF]

Arab Journal of Mathematical Sciences
Purpose – This paper aims to study almost Ricci–Yamabe soliton in the context of certain contact metric manifolds. Design/methodology/approach – The paper is designed as follows: In Section 3, a complete contact metric manifold with the Reeb vector field
Mohan Khatri, Jay Prakash Singh
doaj   +1 more source

Strongly pseudo-convex CR space forms

Complex Manifolds, 2019
For a contact manifold, we study a strongly pseudo-convex CR space form with constant holomorphic sectional curvature for the Tanaka-Webster connection.
Cho Jong Taek
doaj   +1 more source

Nonlinear Obata type equation on Finsler manifolds without boundary

Open Mathematics
We show that if there is a nonconstant function f ∈ C 1,α (M) satisfying the Obata equation on a Finsler n-manifold (M, F), then (M, F) is isometric to a Finsler n-sphere.
Wang Huarong
doaj   +1 more source

Rigidity of Weak Einstein-Randers Spaces [PDF]

Sahand Communications in Mathematical Analysis
The Randers metrics are popular metrics similar to the Riemannian metrics, frequently used in physical and geometric studies. The weak Einstein-Finsler metrics are a natural generalization of the Einstein-Finsler metrics.
Behnaz Lajmiri, Behroz Bidabad, Mehdi Rafie-Rad   +2 more
doaj   +1 more source

Almost Conformal Vector Fields on a Riemannian Manifold

Mathematics
We introduce the notion of an almost conformal vector field, which generalizes conformal vector fields and recently introduced m-modified conformal vector fields on a Riemannian manifold.
Sharief Deshmukh, Hana Al-Sodais
doaj   +1 more source

Robustness of muscle synergies during visuomotor adaptation

Frontiers in Computational Neuroscience, 2013
During visuomotor adaptation a novel mapping between visual targets and motor commands is gradually acquired. How muscle activation patterns are affected by this process is an open question.
Reinhard eGentner, Timothy eEdmunds, Dinesh K Pai, Andrea eD'avella   +3 more
doaj   +1 more source

Coding of hypersurfaces in Euclidean spaces by a constant vector

Open Mathematics
An nn-dimensional Riemannian manifold (Nn,g)({N}^{n},g) isometrically immersed in Euclidean space Rn+1{R}^{n+1} with unit normal ζ\zeta and shape operator SS, for a fixed constant unit vector a→\overrightarrow{{\bf{a}}} in Rn+1{R}^{n+1} induces a vector
Deshmukh Sharief, Guediri Mohammed
doaj   +1 more source