The Experts below are selected from a list of 5073 Experts worldwide ranked by ideXlab platform
Giuseppe Stancarone - One of the best experts on this subject based on the ideXlab platform.
-
On Finsler spacetimes with a timelike Killing Vector Field
Classical and Quantum Gravity, 2018Co-Authors: Erasmo Caponio, Giuseppe StancaroneAbstract:We study Finsler spacetimes and Killing Vector Fields taking care of the fact that the generalised metric tensor associated to the Lorentz–Finsler function L is in general well defined only on a subset of the slit tangent bundle. We then introduce a new class of Finsler spacetimes endowed with a timelike Killing Vector Field that we call stationary splitting Finsler spacetimes. We characterize when a Finsler spacetime with a timelike Killing Vector Field is locally a stationary splitting. Finally, we show that the causal structure of a stationary splitting is the same of one of two Finslerian static spacetimes naturally associated to the stationary splitting.
Erasmo Caponio - One of the best experts on this subject based on the ideXlab platform.
-
On Finsler spacetimes with a timelike Killing Vector Field
Classical and Quantum Gravity, 2018Co-Authors: Erasmo Caponio, Giuseppe StancaroneAbstract:We study Finsler spacetimes and Killing Vector Fields taking care of the fact that the generalised metric tensor associated to the Lorentz–Finsler function L is in general well defined only on a subset of the slit tangent bundle. We then introduce a new class of Finsler spacetimes endowed with a timelike Killing Vector Field that we call stationary splitting Finsler spacetimes. We characterize when a Finsler spacetime with a timelike Killing Vector Field is locally a stationary splitting. Finally, we show that the causal structure of a stationary splitting is the same of one of two Finslerian static spacetimes naturally associated to the stationary splitting.
-
an intrinsic fermat principle on stationary lorentzian manifolds and applications
Differential Geometry and Its Applications, 2002Co-Authors: Erasmo CaponioAbstract:Abstract In this paper a Fermat principle for Lorentzian manifold endowed with a timelike Killing Vector Field is formulated. This principle is applied to obtain existence and multiplicity results on the number of light rays joining an event with an integral curve of the Killing Vector Field.
Jurgen Riedel - One of the best experts on this subject based on the ideXlab platform.
-
self interacting boson stars with a single Killing Vector Field in anti de sitter space time
Physical Review D, 2015Co-Authors: Yves Brihaye, Betti Hartmann, Jurgen RiedelAbstract:We construct rotating boson stars in (4+1)-dimensional asymptotically Anti-de Sitter space-time (aAdS) with two equal angular momenta that are composed out of a massive and self-interacting scalar Field. These solutions possess a single Killing Vector Field. Next to the fundamental solutions radially excited rotating boson stars exist. We find that the behaviour of the solutions for small angular momenta is very well described by the corresponding oscillons. We also discuss the classical stability and find that self-interacting rotating boson stars in aAdS are classically unstable for a large range of the gravitational coupling and the Antide Sitter radius, respectively, can – however – be classically stable for sufficiently large angular momenta. Furthermore, very compact boson stars suffer from a superradiant instability. Our results indicate that this superradiant instability appears only for classically unstable solutions.
Metin Gürses - One of the best experts on this subject based on the ideXlab platform.
-
Killing Vector Fields in Three Dimensions: A Method to Solve Massive Gravity Field Equations
Classical and Quantum Gravity, 2010Co-Authors: Metin GürsesAbstract:Killing Vector Fields in three dimensions play important role in the construction of the related spacetime geometry. In this work we show that when a three dimensional geometry admits a Killing Vector Field then the Ricci tensor of the geometry is determined in terms of the Killing Vector Field and its scalars. In this way we can generate all products and covariant derivatives at any order of the ricci tensor. Using this property we give ways of solving the Field equations of Topologically Massive Gravity (TMG) and New Massive Gravity (NMG) introduced recently. In particular when the scalars of the Killing Vector Field (timelike, spacelike and null cases) are constants then all three dimensional symmetric tensors of the geometry, the ricci and einstein tensors, their covariant derivatives at all orders, their products of all orders are completely determined by the Killing Vector Field and the metric. Hence the corresponding three dimensional metrics are strong candidates of solving all higher derivative gravitational Field equations in three dimensions.
-
Killing Vector Fields in three dimensions a method to solve massive gravity Field equations
Classical and Quantum Gravity, 2010Co-Authors: Metin GürsesAbstract:Killing Vector Fields in three dimensions play an important role in the construction of the related spacetime geometry. In this work we show that when a three-dimensional geometry admits a Killing Vector Field then the Ricci tensor of the geometry is determined in terms of the Killing Vector Field and its scalars. In this way we can generate all products and covariant derivatives at any order of the Ricci tensor. Using this property we give ways to solve the Field equations of topologically massive gravity (TMG) and new massive gravity (NMG) introduced recently. In particular when the scalars of the Killing Vector Field (timelike, spacelike and null cases) are constants then all three-dimensional symmetric tensors of the geometry, the Ricci and Einstein tensors, their covariant derivatives at all orders, and their products of all orders are completely determined by the Killing Vector Field and the metric. Hence, the corresponding three-dimensional metrics are strong candidates for solving all higher derivative gravitational Field equations in three dimensions.
V Moncrief - One of the best experts on this subject based on the ideXlab platform.
-
On spacetimes containing Killing Vector Fields with non-closed orbits
Classical and Quantum Gravity, 1992Co-Authors: J Isenberg, V MoncriefAbstract:The authors show that if a maximally extended, globally hyperbolic solution of Einstein's equations admits a non-vanishing Killing Vector Field which is tangent to a compact Cauchy surface and which has non-closed orbits, then the spacetime isometry group is at least two dimensional.
