Zobrazeno 1 - 10
of 5 791
pro vyhledávání: '"sectional curvature"'
Autor:
Noura Alhouiti
Publikováno v:
AIMS Mathematics, Vol 9, Iss 7, Pp 17489-17503 (2024)
The present paper aims to demonstrate the theorems of existence and uniqueness for pointwise slant immersions in Kenmotsu space forms. Some substantial results are given in this direction. Also, we offer non-trivial examples of pointwise slant subman
Externí odkaz:
https://doaj.org/article/2ece6bc808014f82a50a4e1326f6583e
Autor:
S. E. Stepanov, I. I. Tsyganok
Publikováno v:
Дифференциальная геометрия многообразий фигур, Vol 55, Iss 1, Pp 68-73 (2024)
In the present paper, we prove that if is an -dimensional compact Riemannian manifold and if where , and are the sectional and Ricci curvatures of respectively, then is diffeomorphic to a spherical space form where is a finite group of isometries act
Externí odkaz:
https://doaj.org/article/fa435ea2010045c68d3752561b127c43
Autor:
Yayun Chen, Tongzhu Li
Publikováno v:
AIMS Mathematics, Vol 8, Iss 10, Pp 23247-23271 (2023)
Let $ f: M^n\to \mathbb{R}^{n+1}_1 $ be an $ n $-dimensional umbilic-free spacelike hypersurface in the $ (n+1) $-dimensional Lorentzian space $ \mathbb{R}^{n+1}_1 $ with an induced metric $ I $. Let $ II $ be the second fundamental form and $ H $ th
Externí odkaz:
https://doaj.org/article/891c5ff954b04b09a86dbb52f6ae444b
Autor:
Noura Alhouiti
Publikováno v:
AIMS Mathematics, Vol 8, Iss 8, Pp 17470-178483 (2023)
In this paper we derive the Existence and Uniqueness Theorems for pointwise slant immersions in Sasakian space forms which extend the Existence and Uniqueness Theorems for slant immersions in Sasakian space forms proved by Cabreizo et al in 2001.
Externí odkaz:
https://doaj.org/article/f654f5e05b3443089589c86b03e7ad8a
Autor:
Belot, Gordon, author
Publikováno v:
Accelerating Expansion : Philosophy and Physics with a Positive Cosmological Constant, 2023, ill.
Externí odkaz:
https://doi.org/10.1093/oso/9780192866462.003.0004
Autor:
S. V. Galaev
Publikováno v:
Дифференциальная геометрия многообразий фигур, Vol 54, Iss 1, Pp 64-77 (2023)
In this article, a sub-Riemannian manifold of contact type is understood as a Riemannian manifold equipped with a regular distribution of codimension-one and by a unit structure vector field orthogonal to this distribution. This vector field is cal
Externí odkaz:
https://doaj.org/article/d389b89a159346a6ac1820b1f0b66107
Autor:
S. E. Stepanov, I. I. Tsyganok
Publikováno v:
Дифференциальная геометрия многообразий фигур, Vol 54, Iss 2, Pp 45-53 (2023)
In the present paper we consider pointwise orthogonal splitting of the space of well-known TT-tensors on Riemannian manifolds. Tensors of the first subspace belong to the kernel of the Bourguignon Laplacian, and the tensors of the second subs
Externí odkaz:
https://doaj.org/article/5a8b155be9bf4c7da73e90a61ca601fc
Autor:
Graham Hall
Publikováno v:
Symmetry, Vol 16, Iss 2, p 230 (2024)
This paper presents a brief study of (2-dimensional, spacelike) wave surfaces to a null direction l on a space-time (M,g) and studies how certain imposed symmetries on the set of such wave surfaces can be used to describe other geometrical features o
Externí odkaz:
https://doaj.org/article/086054fd85544d5c9643bc628faaa3a3