Results 41 to 50 of about 436 (165)

Geodesic Mappings of Semi-Riemannian Manifolds with a Degenerate Metric

Mathematics, 2022
This article introduces the concept of geodesic mappings of manifolds with idempotent pseudo-connections. The basic equations of canonical geodesic mappings of manifolds with completely idempotent pseudo-connectivity and semi-Riemannian manifolds with a ...
Igor G. Shandra, Josef Mikeš
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On general helices and pseudo-riemannian manifolds

Communications, Faculty Of Science, University of Ankara Series A1Mathematics and Statistics, 1998
In a Riemannian manifold, a regular curve is called a general helix if is constant and its firs and second curvatures are not constant [4]. If its First and second curvatures are constant the third curvature is zero then the regular curve is called helix. For helices in a Lorentzian manifold, there is a research of T.
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ON THE LIFTS OF SEMI-RIEMANNIAN METRICS [PDF]

Journal of Sciences, Islamic Republic of Iran, 1994
In this paper, we extend Sasaki metric for tangent bundle of a Riemannian manifold and Sasaki-Mok metric for the frame bundle of a Riemannian manifold [I] to the case of a semi-Riemannian vector bundle over a semi- Riemannian manifold. In fact, if E is a
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Towards a Geometrization of Renormalization Group Histories in Asymptotic Safety

Universe, 2021
Considering the scale-dependent effective spacetimes implied by the functional renormalization group in d-dimensional quantum Einstein gravity, we discuss the representation of entire evolution histories by means of a single, (d+1)-dimensional manifold ...
Renata Ferrero, Martin Reuter
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The action of pseudo-differential operators on functions harmonic outside a smooth hyper-surface

Comptes Rendus. Mathématique
The goal of this note is to describe the action of pseudo-differential operators on the space of square integrable functions which are harmonic outside a smooth closed hyper-surface of a compact Riemannian manifold.
Boutet de Monvel, Louis, Colin de Verdière, Yves   +1 more
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Solitons on pseudo-Riemannian manifolds: stability and motion [PDF]

Electronic Research Announcements of the American Mathematical Society, 2000
This is an announcement of results concerning a class of solitary wave solutions to semilinear wave equations. The solitary waves studied are solutions of the form ϕ ( t , x ) = e i ω t f ω (
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On the Non Metrizability of Berwald Finsler Spacetimes

Universe, 2020
We investigate whether Szabo’s metrizability theorem can be extended to Finsler spaces of indefinite signature. For smooth, positive definite Finsler metrics, this important theorem states that, if the metric is of Berwald type (i.e., its Chern–Rund ...
Andrea Fuster, Sjors Heefer, Christian Pfeifer, Nicoleta Voicu   +3 more
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Pseudo-Reimannian manifolds endowed with an almost para f-structure

International Journal of Mathematics and Mathematical Sciences, 1985
Let M˜(U,Ω˜,η˜,ξ,g˜) be a pseudo-Riemannian manifold of signature (n+1,n). One defines on M˜ an almost cosymplectic para f-structure and proves that a manifold M˜ endowed with such a structure is ξ-Ricci flat and is foliated by minimal hypersurfaces ...
Vladislav V. Goldberg, Radu Rosca
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Torsional Newton Cartan gravity from non-relativistic strings

Journal of High Energy Physics, 2020
We study propagation of closed bosonic strings in torsional Newton-Cartan geometry based on a recently proposed Polyakov type action derived by dimensional reduction of the ordinary bosonic string along a null direction. We generalize the Polyakov action
A.D. Gallegos, U. Gürsoy, N. Zinnato
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Higher-order Jordan Osserman pseudo-Riemannian manifolds [PDF]

Classical and Quantum Gravity, 2002
We study the higher order Jacobi operator in pseudo-Riemannian geometry. We exhibit a family of manifolds so that this operator has constant Jordan normal form on the Grassmannian of subspaces of signature (r,s) for certain values of (r,s). These pseudo-Riemannian manifolds are new and non-trivial examples of higher order Osserman manifolds.
Gilkey, Peter B., Ivanova, Raina, Zhang, Tan   +2 more
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