Powers of the space forms curvature operator and geodesics of the tangent bundle (original) (raw)

The projective curvature of the tangent bundle with natural diagonal metric

Filomat, 2015

Our study is mainly devoted to a natural diagonal metric G on the total space TMof the tangent bundle of a Riemannian manifold (M, 1). We provide the necessary and sufficient conditions under which (TM,G) is a space form, or equivalently (TM,G) is projectively Euclidean. Moreover, we classify the natural diagonal metrics G for which (TM,G) is horizontally projectively flat (resp. vertically projectively flat).

On geodesics of Berger tangent sphere bundle of Hermitian locally symmetric manifold

We propose a special deformation of the Sasaki metric on tangent and unit tangent bundle of a Hermitian locally symmetric manifold. Geodesics of this deformed metric have different projections on a base manifold for tangent or unit tangent bundle cases in contrast to usual Sasaki metric. Nevertheless, the projections of geodesics of the unit tangent bundle still preserve the property to have all geodesic curvatures constant.

Some Aspects on the Geometry of the Tangent Bundles and Tangent Sphere Bundles of a Riemannian Manifold

Mediterranean Journal of Mathematics, 2008

In this paper we study a Riemanian metric on the tangent bundle T (M ) of a Riemannian manifold M which generalizes Sasaki metric and Cheeger Gromoll metric and a compatible almost complex structure which together with the metric confers to T (M ) a structure of locally conformal almost Kählerian manifold. This is the natural generalization of the well known almost Kählerian structure on T (M ). We found conditions under which T (M ) is almost Kählerian, locally conformal Kählerian or Kählerian or when T (M ) has constant sectional curvature or constant scalar curvature. Then we will restrict to the unit tangent bundle and we find an isometry with the tangent sphere bundle (not necessary unitary) endowed with the restriction of the Sasaki metric from T (M ). Moreover, we found that this map preserves also the natural almost contact structures obtained from the almost Hermitian ambient structures on the unit tangent bundle and the tangent sphere bundle, respectively.

On the Tangent Sphere Bundle with the Sasaki Semi Riemann Metric of a Space Form

2014

In this paper, the Sasaki semi Riemann metric gS on the tangent sphere bundle with radius ε TεS 1 of the unit 2-sphere S 2 1 in semi Euclidean space E 3 1 is obtained . In addition, the connection coefficients of the Levi Civita connection on the semi Riemann manifold (TεS 1, g S) are found. Furthermore, a non-linear differential equation’s system which gives geodesics of TεS 1 is obtained. Finally, the components of the Riemann curvature tensor of TεS 1 are calculated. MSC 2010: 55R25, 53C25.

Some Problems Concerning with Sasaki Metric on the Second-Order Tangent Bundles

International Electronic Journal of Geometry, 2020

In this paper, we consider a second-order tangent bundle equipped with Sasaki metric over a Riemannian manifold. All forms of curvature tensor fields are computed. We obtained the relation between the scalar curvature of the base manifold and the scalar curvature of the second-order tangent bundle and presented some geometric results concerning with kinds of curvature tensor fields. Also, we search the weakly symmetry property of the second-order tangent bundle. Finally, we end our paper with statistical structures on the second-order tangent bundle.

The Holomorphic φ-Sectional Curvature of Tangent Sphere Bundles with Sasakian Structures

Annals of the Alexandru Ioan Cuza University - Mathematics, 2011

We study the holomorphic φ-sectional curvature of the natural diagonal tangent sphere bundles with Sasakian structures, determined by Druţȃ-Romaniuc and Oproiu. After finding the explicit expressions for the components of the curvature tensor field and of the curvature tensor field corresponding to the Sasakian space forms, we find that there are no tangent sphere bundles of natural diagonal lift type of constant holomorphic φ-sectional curvature.

Geodesics on the Tangent Sphere Bundle of 3-SPHERE

2013

The Sasaki Riemann metric gS on the tangent sphere bundle T1S of the unit 3-sphere S3 is obtained by using the geodesic polar coordinate of S3. The connection coefficients of the Levi Civita connection of the Sasaki Riemann manifold ( T1S, gS ) are found. Furthermore, a system of differential equations which gives all geodesics of Sasaki Riemann manifold is obtained.

Geodesicity and Isoclinity Properties for the Tangent Bundle of the Heisenberg Manifold with Sasaki Metric

arXiv: Differential Geometry, 2010

We prove that the horizontal and vertical distributions of the tangent bundle with the Sasaki metric are isocline, the distributions given by the kernels of the horizontal and vertical lifts of the contact form omega\omegaomega from the Heisenberg manifold (H3,g)(H_3,g)(H3,g) to (TH3,gS)(TH_3,g^S)(TH3,gS) are not totally geodesic, and the distributions FH=L(E1H,E2H)F^H=L(E_1^H,E_2^H)FH=L(E1H,E2H) and FV=L(E1V,E2V)F^V=L(E_1^V,E_2^V)FV=L(E1V,E2V) are totally geodesic, but they are not isocline. We obtain that the horizontal and natural lifts of the curves from the Heisenberg manifold (H_3,g)(H_3,g)(H3,g), are geodesics in the tangent bundle endowed with the Sasaki metric (TH3,gs)(TH_3,g^s)(TH3,gs), if and only if the curves considered on the base manifold are geodesics. Then, we get two particular examples of geodesics from (TH3,gs)(TH_3,g^s)(TH3,gs), which are not horizontal or natural lifts of geodesics from the base manifold (H3,g)(H_3,g)(H_3,g).

A note about scalar curvature on the total space of a vector bundle

arXiv: Differential Geometry, 2019

We construct complete Riemannian metrics to show that the total space of tangent bundles of orientable closed surfaces (except torus) admits complete uniformly PSC-metrics. It gives a partial positive answer to one of Gromov's question.