Results 21 to 30 of about 1,284 (79)

Ricci curvature of submanifolds in Kenmotsu space forms

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 12, Page 719-726, 2002., 2002
In 1999, Chen established a sharp relationship between the Ricci curvature and the squared mean curvature for a submanifold in a Riemannian space form with arbitrary codimension. Similar problems for submanifolds in complex space forms were studied by Matsumoto et al.
Kadri Arslan   +4 more
wiley   +1 more source

Weak helix submanifolds of euclidean spaces [PDF]

open access: yes, 2009
It is shown that there exist nonstrong weak 2-helix surfaces of ...
A.J. Di Scala   +7 more
core   +1 more source

Global pinching theorems of submanifolds in spheres

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 3, Page 183-191, 2002., 2002
Let M be a compact embedded submanifold with parallel mean curvature vector and positive Ricci curvature in the unit sphere S n+p(n ≥ 2 , p ≥ 1). By using the Sobolev inequalities of P. Li (1980) to Lp estimate for the square length σ of the second fundamental form and the norm of a tensor Φ, related to the second fundamental form, we set up some ...
Kairen Cai
wiley   +1 more source

On the number of optimal surfaces [PDF]

open access: yes, 2008
Let X be a closed oriented Riemann surface of genus > 1 of constant negative curvature -1. A surface containing a disk of maximal radius is an optimal surface.
Vdovina, Alina
core   +3 more sources

On hypersurfaces in a locally affine Riemannian Banach manifold

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 6, Page 375-379, 2002., 2002
We prove that an essential hypersurface of second order in an infinite dimensional locally affine Riemannian Banach manifold is a Riemannian manifold of constant nonzero curvature.
El-Said R. Lashin, Tarek F. Mersal
wiley   +1 more source

CR‐submanifolds of a nearly trans‐Sasakian manifold

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 3, Page 167-175, 2002., 2002
This paper considers the study of CR‐submanifolds of a nearly trans‐Sasakian manifold, generalizing the results of trans‐Sasakian manifolds and thus those of Sasakian manifolds.
Falleh R. Al-Solamy
wiley   +1 more source

Submanifolds of F‐structure manifold satisfying FK + (−)K+1F = 0

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 3, Page 167-172, 2001., 2001
The purpose of this paper is to study invariant submanifolds of an n‐dimensional manifold M endowed with an F‐structure satisfying FK + (−)K+1F = 0 and FW + (−)W+1F ≠ 0 for 1 < W < K, where K is a fixed positive integer greater than 2. The case when K is odd (≥3) has been considered in this paper.
Lovejoy S. Das
wiley   +1 more source

On real hypersurfaces in quaternionic projective space with 𝒟⊥‐recurrent second fundamental tensor

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 22, Issue 1, Page 109-117, 1999., 1999
In this paper, we give a complete classification of real hypersurfaces in a quaternionic projective space QPm with 𝒟⊥‐recurrent second fundamental tensor under certain condition on the orthogonal distribution 𝒟.
Young Jin Suh, Juan De Dios Pérez
wiley   +1 more source

On Chen invariants and inequalities in quaternionic geometry

open access: yes, 2013
In this paper we give a survey of main results concerning Chen inequalities for submanifolds in quaternionic space forms and propose some open problems in the field for further research.AMS Subject Classification:53C15, 53C25, 53C40.
G. Vîlcu
semanticscholar   +1 more source

Totally real submanifolds in a complex projective space

open access: yesInternational Journal of Mathematics and Mathematical Sciences, Volume 22, Issue 1, Page 205-208, 1999., 1999
In this paper, we establish the following result: Let M be an n‐dimensional complete totally real minimal submanifold immersed in CPn with Ricci curvature bounded from below. Then either M is totally geodesic or inf r ≤ (3n + 1)(n − 2)/3, where r is the scalar curvature of M.
Liu Ximin
wiley   +1 more source

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