Results 21 to 30 of about 10,692 (245)
On geodesic mappings of symmetric pairs
Pracì Mìžnarodnogo Geometričnogo Centru, 2023 The paper treats properties of pseudo-Riemannian spaces admitting non-trivial geodesic mappings. A symmetric pair of pseudo-Riemannian spaces is a pair of spaces with coinciding values of covariant derivatives for their Riemann tensors. It is proved that
Volodymyr Kiosak +2 more
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On the Maldacena Type Conjecture in Relation with Scale Relativity Theory [PDF]
Memoirs of the Scientific Sections of the Romanian Academy, 2022 A Maldacena type conjecture in relation with Scale Relativity Theory using Schrödinger representations of fractal type dynamics of any physical system is proposed. The operational procedure developed by the authors is based on the phase coherences of the
Alexandra Saviuc +2 more
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A Geometry Preserving Kernel over Riemannian Manifolds [PDF]
Journal of Artificial Intelligence and Data Mining, 2018 - Kernel trick and projection to tangent spaces are two choices for linearizing the data points lying on Riemannian manifolds. These approaches are used to provide the prerequisites for applying standard machine learning methods on Riemannian manifolds ...
Kh. Sadatnejad +2 more
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A Note on the Geometry of Certain Classes of Lichnerowicz Laplacians and Their Applications
Mathematics, 2023 In the present paper, we prove vanishing theorems for the null space of the Lichnerowicz Laplacian acting on symmetric two tensors on complete and closed Riemannian manifolds and further estimate its lowest eigenvalue on closed Riemannian manifolds.
Vladimir Rovenski +2 more
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Polar Actions on Berger Spheres [PDF]
, 2006 The object of this article is to study a torus action on a so-called Berger sphere. We also make some comments on polar actions on naturally reductive homogeneous spaces. Finally, we prove a rigidity-type theorem for Riemannian manifolds carrying a polar
ANTONIO J. DI SCALA +1 more
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Approximate Lie Symmetry Conditions of Autoparallels and Geodesics
Abstract and Applied Analysis, 2020 This paper is devoted to the study of approximate Lie point symmetries of general autoparallel systems. The significance of such systems is that they characterize the equations of motion of a Riemannian space under an affine parametrization.
Sameerah Jamal
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Dynamic and low-dimensional modeling of brain functional connectivity on Riemannian manifolds
NeuroImageModeling brain functional connectivity (FC) is key in investigating brain functions and dysfunctions. FC is typically quantified by symmetric positive definite (SPD) matrices that are located on a Riemannian manifold rather than the regular Euclidean ...
Mingyu Wang, Yueming Wang, Yuxiao Yang
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Riemannian submersions From Almost Hermitian Manifolds
, 2017 In this chapter, we introduce various new Riemannian submersions from almost Hermitian manifolds on to Riemannian manifolds. In section 1, we first review almost Hermitian manifolds and their submanifolds, and give brief information about holomorphic ...
Sahin, Bayram, Bayram Şahin
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A spinorial energy functional: Critical points and gradient flow
, 2012 On the universal bundle of unit spinors we study a natural energy functional whose critical points, if dimM C 3, are precisely the pairs (g,φ) consisting of a Ricci-flat Riemannian metric g together with a parallel g-spinor φ.
Hartmut Weiss +5 more
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On Pseudo-Petrov Symmetric Riemannian Manifolds
Advances in Mathematical Physics, 2016 The present paper deals with pseudo-Petrov symmetric Riemannian manifolds whose space-matter tensor satisfies a special condition. Firstly, basic results of pseudo-Petrov symmetric Riemannian manifolds are obtained.
Sanjib Kumar Jana +3 more
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