Results 11 to 20 of about 201,081 (270)
Homogeneous spaces of unsolvable Lie groups that do not admit equiaffine connections of nonzero curvature [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2023 An important subclass among homogeneous spaces is formed by isotropically-faithful homogeneous spaces, in particular, this subclass contains all homogeneous spaces admitting invariant affine connection.
Mozhey, Natalya Pavlovna
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Curvature invariants in type- N spacetimes [PDF]
Classical and Quantum Gravity, 1998 Scalar curvature invariants are studied in type N solutions of vacuum Einstein's equations with in general non-vanishing cosmological constant Lambda. Zero-order invariants which include only the metric and Weyl (Riemann) tensor either vanish, or are constants depending on Lambda. Even all higher-order invariants containing covariant derivatives of the
Bicak, J., Pravda, V.
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The commutative nonassociative algebra of metric curvature tensors
Forum of Mathematics, Sigma, 2021 The space of tensors of metric curvature type on a Euclidean vector space carries a two-parameter family of orthogonally invariant commutative nonassociative multiplications invariant with respect to the symmetric bilinear form determined by the metric ...
Daniel J. F. Fox
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CURVATURE INVARIANTS IN ALGEBRAICALLY SPECIAL SPACETIMES [PDF]
The Ninth Marcel Grossmann Meeting, 2002 It is well known that all curvature invariants of the order zero vanish for type-III and type-N vacuum spacetimes. We briefly summarize properties of higher order curvature invariants for these spacetimes.
Pravda, V., Bicak, J.
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Universality and Constant Scalar Curvature Invariants [PDF]
ISRN Geometry, 2011 A classical solution is called universal if the quantum correction is a multiple of the metric. Therefore, universal solutions play an important role in the quantum theory. We show that in a spacetime which is universal all scalar curvature invariants are constant (i.e., the spacetime is CSI).
Coley, A. A., Hervik, S.
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Pseudoparallel invariant submanifolds of Kenmotsu manifolds
Journal of Amasya University the Institute of Sciences and Technology, 2023 In this paper, we consider pseudoparallel invariant submanifolds, a particular class of invariant submanifolds of Kenmotsu manifolds, on $W_8$ curvature tensor and investigate some of their basic characterizations, such as $W_8$ pseudoparallel, $W_8$-2 ...
Nurnisa Karaman, Mehmet Atçeken
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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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Non-coercive Ricci flow invariant curvature cones [PDF]
Proceedings of the American Mathematical Society, 2015 16 pages, comments are ...
Richard, Thomas, Seshadri, Harish
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CURVATURE APPROXIMATION FROM PARABOLIC SECTORS
Image Analysis and Stereology, 2017 We propose an invariant three-point curvature approximation for plane curves based on the arc of a parabolic sector, and we analyze how closely this approximation is to the true curvature of the curve.
Ximo Gual-Arnau +2 more
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Disformal invariance of curvature perturbation [PDF]
Journal of Cosmology and Astroparticle Physics, 2016 We show that under a general disformal transformation the linear comoving curvature perturbation is not identically invariant, but is invariant on superhorizon scales for any theory that is disformally related to Horndeski's theory. The difference between disformally related curvature perturbations is found to be given in terms of the comoving density ...
Motohashi, Hayato, White, Jonathan
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