Results 21 to 30 of about 7,082 (264)

Memory effects in Kundt wave spacetimes

Physics Letters B, 2020
Memory effects in the exact Kundt wave spacetimes are shown to arise in the behaviour of geodesics in such spacetimes. The types of Kundt spacetimes we consider here are direct products of the form H2×M(1,1) and S2×M(1,1).
Indranil Chakraborty, Sayan Kar
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Generalized disformal invariance of cosmological perturbations with second-order field derivatives

Physics Letters B, 2021
We investigate how the comoving curvature and tensor perturbations are transformed under the generalized disformal transformation with the second-order covariant derivatives of the scalar field, where the free functions depend on the fundamental elements
Masato Minamitsuji
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On the transverse Scalar Curvature of a Compact Sasaki Manifold

Complex Manifolds, 2014
We show that the standard picture regarding the notion of stability of constant scalar curvature metrics in Kähler geometry described by S.K. Donaldson [10, 11], which involves the geometry of infinitedimensional groups and spaces, can be applied to the ...
He Weiyong
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Metric Inequalities with Scalar Curvature [PDF]

Geometric and Functional Analysis, 2018
We establish several inequalities for manifolds with positive scalar curvature and, more generally, for the scalar curvature bounded from below, in the spirit of the classical bound on the distances between conjugates points in surfaces with positive sectional curvature.
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Boundary Conditions for Scalar Curvature

, 2023
Minor typos fixed.
Baer, Christian, Hanke, Bernhard
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Heterotic reduction of Courant algebroid connections and Einstein–Hilbert actions

Nuclear Physics B, 2016
We discuss Levi-Civita connections on Courant algebroids. We define an appropriate generalization of the curvature tensor and compute the corresponding scalar curvatures in the exact and heterotic case, leading to generalized (bosonic) Einstein–Hilbert ...
Branislav Jurčo, Jan Vysoký
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On the scalar curvature and sectional curvatures of a Kaehler submanifold [PDF]

Proceedings of the American Mathematical Society, 1973
For a Kaehler submanifold of a complex space form, pinching for scalar curvature implies pinching for sectional curvatures. 1 . Statement of result. The scalar curvature is, by definition, the sum of Ricci curvatures with respect to an orthonormal basis of the tangent space, and the Ricci curvature is the sum of sectional curvatures.
Chen, Bang-Yen, Ogiue, Koichi
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Two dimensional kinematic surfaces with constant scalar curvature in Lorentz-Minkowski 7-space

Nonlinear Engineering, 2017
In this paper we analyzed the problem of studying locally the scalar curvature S of the two dimensional kinematic surfaces obtained by the homothetic motion of a helix in Lorentz-Minkowski space E17 $\text{E}^7_1$ .
Solouma E. M., Wageeda M. M.
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Curvature operators and scalar curvature invariants [PDF]

Classical and Quantum Gravity, 2010
We continue the study of the question of when a pseudo-Riemannain manifold can be locally characterised by its scalar polynomial curvature invariants (constructed from the Riemann tensor and its covariant derivatives). We make further use of alignment theory and the bivector form of the Weyl operator in higher dimensions, and introduce the important ...
Hervik, Sigbjørn, Coley, Alan
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Scalar Curvature via Local Extent

Analysis and Geometry in Metric Spaces, 2018
We give a metric characterization of the scalar curvature of a smooth Riemannian manifold, analyzing the maximal distance between (n + 1) points in infinitesimally small neighborhoods of a point.
Veronelli Giona
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