Results 31 to 40 of about 1,461,044 (179)
Time-Dependent 2-D Vector Field Topology: An Approach Inspired by Lagrangian Coherent Structures
, 2010 This paper presents an approach to a time-dependent variant of the concept of vector field topology for 2-D vector fields. Vector field topology is defined for steady vector fields and aims at discriminating the domain of a vector field into regions of ...
Eberly +18 more
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Averaged energy conditions for vector fields
Physics Letters B, 2023 In this work we shall obtain sufficient conditions for the appearance of singularities in gravitational theories which propagate an extra vector degree of freedom, based on the known relaxations of the singularity theorems.
Francisco José Maldonado Torralba
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Liftable derivations for generically separably algebraic morphisms of schemes
, 2006 We consider dominant, generically algebraic, and tamely ramified (if the characteristic is positive) morphisms $\pi: X/S \to Y/S$, where Y,S are Noetherian and integral and X is a Krull scheme (e.g.
Källström, Rolf
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On generic homogeneous vector fields
Известия высших учебных заведений. Поволжский регион: Физико-математические науки, 2022 Background. The study of dynamical systems with symmetry is of both theoretical and applied interest. Phase portraits of dynamical systems defined by homogeneous vector fields are invariant with respect to the phase space dilation group.
V.Sh. Roytenberg
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Existence of periodic orbits for geodesible vector fields on closed 3-manifolds
, 2009 In this paper we deal with the existence of periodic orbits of geodesible vector fields on closed 3-manifolds. A vector field is geodesible if there exists a Riemannian metric on the ambient manifold making its orbits geodesics.
Rechtman, Ana
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A vector field approach to calculating gravitational forces
New Journal of Physics, 2017 Calculation of gravitational forces is essential for many fundamental measurements, such as determining the gravitational constant or investigating violations of the inverse square law.
Julian Stirling
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Inflation with Massive Vector Fields
, 2015 We investigate the coupling between the inflaton and massive vector fields. All renormalizable couplings with shift symmetry of the inflaton are considered. The massive vector can be decomposed into a scalar mode and a divergence-free vector mode.
Liu, Junyu, Wang, Yi, Zhou, Siyi
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Classical observer form for discrete-time nonlinear system: MIMO case [PDF]
Proceedings of the Estonian Academy of SciencesThe paper addresses the problem of transforming multi-input multi-output discrete-time nonlinear state equations into the classical observer form using state transformation.
Arvo Kaldmäe +4 more
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MathematicsWe continue studying the σ-Ricci vector field u on a Riemannian manifold (Nm,g), which is not necessarily closed. A Riemannian manifold with Ricci operator T, a Coddazi-type tensor, is called a T-manifold.
Hanan Alohali +2 more
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Vector Fields in Holographic Cosmology
, 2013 We extend the holographic formulation of the semiclassical no-boundary wave function (NBWF) to models with Maxwell vector fields. It is shown that the familiar saddle points of the NBWF have a representation in which a regular, Euclidean asymptotic AdS ...
Hartle, James B. +2 more
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