Results 71 to 80 of about 94,728 (213)

The Feller property on Riemannian manifolds

Journal of Functional Analysis, 2012
The asymptotic behavior of the heat kernel of a Riemannian manifold gives rise to the classical concepts of parabolicity, stochastic completeness (or conservative property) and Feller property (or $C^{0}$-diffusion property). Both parabolicity and stochastic completeness have been the subject of a systematic study which led to discovering not only ...
PIGOLA, STEFANO, SETTI, ALBERTO GIULIO
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The left-invariant contact metric structure on the Sol manifold

Учёные записки Казанского университета: Серия Физико-математические науки, 2020
Among the known eight-dimensional Thurston geometries, there is a geometry of the Sol manifold – a Lie group consisting of real special matrices. For a left-invariant Riemannian metric on the Sol manifold, the left shift group is a maximal simple ...
V.I. Pan’zhenskii, A.O. Rastrepina
doaj   +1 more source

Regular curves on Riemannian manifolds [PDF]

Transactions of the American Mathematical Society, 1958
Introduction. A regular curve on a Riemannian manifold is a curve with a continuously turning nontrivial tangent vector.(2) A regular homotopy is a homotopy which at every stage is a regular curve, keeps end points and directions fixed and such that the tangent vector moves continuously with the homotopy.
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Four-dimensional Riemannian product manifolds with circulant structures

, 2019
A 4-dimensional Riemannian manifold equipped with an additional tensor structure, whose fourth power is the identity, is considered. This structure has a circulant matrix with respect to some basis, i.e.
Dokuzova, Iva
core  

Two theorems on (ϵ)-Sasakian manifolds

International Journal of Mathematics and Mathematical Sciences, 1998
In this paper, We prove that every (ϵ)-sasakian manifold is a hypersurface of an indefinite kaehlerian manifold, and give a necessary and sufficient condition for a Riemannian manifold to be an (ϵ)-sasakian manifold.
Xu Xufeng, Chao Xiaoli
doaj   +1 more source

Characterizing Humans on Riemannian Manifolds

IEEE Transactions on Pattern Analysis and Machine Intelligence, 2013
In surveillance applications, head and body orientation of people is of primary importance for assessing many behavioral traits. Unfortunately, in this context people are often encoded by a few, noisy pixels so that their characterization is difficult.
TOSATO, DIEGO, SPERA, Mauro, CRISTANI, Marco, MURINO, Vittorio   +3 more
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A note on closed vector fields

AIMS Mathematics
Special vector fields, such as conformal vector fields and Killing vector fields, are commonly used in studying the geometry of a Riemannian manifold. Though there are Riemannian manifolds, which do not admit certain conformal vector fields or certain ...
Nasser Bin Turki , Sharief Deshmukh , Olga Belova   +2 more
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Degenerate Foliations in Sasakian Semi-Riemannian Manifolds [PDF]

In the Semi-Riemannian case we do not have the liability of the existence of such a metric being a difference from the Riemannian case. A Semi-Riemannian manifold provided with a normal contact metric structure is called Sasakian manifold.Semi-Riemannian,
Catalin Angelo Ioan
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Riemannian $s$-manifolds [PDF]

Journal of Differential Geometry, 1977
Tsagas, Gr., Ledger, A.
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Characterizing Affine Vector Fields on Pseudo-Riemannian Manifolds

Axioms
We study the characteristics of affine vector fields on pseudo-Riemannian manifolds and provide tensorial formulas that characterize these vector fields.
Norah Alshehri, Mohammed Guediri
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