scholarly journals Exact solution of vacuum field equation in Finsler spacetime

2014 ◽  
Vol 90 (6) ◽  
Author(s):  
Xin Li ◽  
Zhe Chang
Keyword(s):  
Exact Solution ◽  
Field Equation ◽  
Vacuum Field ◽  
Finsler Spacetime ◽  
Vacuum Field Equation

ON GRAVITO-ELECTROMAGNETIC DUALITY IN GENERAL RELATIVITY

1999 ◽  
Vol 14 (12) ◽  
pp. 759-763 ◽  
Author(s):  
NARESH DADHICH
Keyword(s):  
General Relativity ◽  
Field Equation ◽  
Gravitational Constant ◽  
Electromagnetic Theory ◽  
Vacuum Field ◽  
Vacuum Equation ◽  
Riemann Curvature ◽  
Duality Transformation ◽  
Duality Symmetry ◽  
Vacuum Field Equation

In analogy with the electromagnetic theory, we resolve the Riemann curvature into electric and magnetic parts and consider the analogous duality transformation which keeps the Einstein action for vacuum invariant. It is remarkable that the duality symmetry of the action also leads to the vacuum field equation without cosmological constant. Further invariance of the vacuum equation and the action under the gravito-electric duality require gravitational constant to change sign.

Linearized Nonlocal Gravity

2017 ◽  
Author(s):  
Bahram Mashhoon
Keyword(s):  
Exact Solution ◽  
Dark Matter ◽  
Gravitational Field ◽  
Field Equation ◽  
Gravitational Lensing ◽  
Modified Gravity ◽  
Trivial Solution ◽  
Minkowski Spacetime ◽  
Linear Regime ◽  
Simple Generalization

The only known exact solution of the field equation of nonlocal gravity (NLG) is the trivial solution involving Minkowski spacetime that indicates the absence of a gravitational field. Therefore, this chapter is devoted to a thorough examination of NLG in the linear approximation beyond Minkowski spacetime. Moreover, the solutions of the linearized field equation of NLG are discussed in detail. We adopt the view that the kernel of the theory must be determined from observation. In the Newtonian regime of NLG, we recover the phenomenological Tohline-Kuhn approach to modified gravity. A simple generalization of the Kuhn kernel leads to a three-parameter modified Newtonian force law that is always attractive. Gravitational lensing is discussed. It is shown that nonlocal gravity (NLG), with a characteristic galactic lengthscale of order 1 kpc, simulates dark matter in the linear regime while preserving causality.

scholarly journals A Bosonisation of QCD and Realisations of Chiral Symmetry

1987 ◽  
Vol 40 (4) ◽  
pp. 499 ◽  
Author(s):  
CD Roberts ◽  
RT Cahill
Keyword(s):  
Symmetry Group ◽  
Chiral Symmetry ◽  
Functional Integral ◽  
Vacuum Field ◽  
Global Symmetry ◽  
Field Representation ◽  
Generating Functional ◽  
Global Symmetry Group ◽  
Vacuum Field Equation ◽  
Alternative Solutions

We employ the functional integral formalism to study quantum chromodynamics (QCD) with Nf quarks of zero bare mass. In addition to local SU(Nc) colour symmetry, this theory possesses exact global G = UdNf)@UR(Nf) chiral symmetry. We obtain an exact bilocal Bose field representation of the generating functional which, as we prove after establishing the manner in which the bilocal fields transform under G, preserves the global chiral symmetry. We demonstrate how a local Bose field representation of the generating functional may be obtained from the bilocal bosonisation. This provides a direct link between QCD and low energy meson phenomenological models. We utilise the bilocal bosonisation in the study of the dynamical breakdown of the global chiral symmetry group G. We derive the vacuum field equation from the exact bilocal Bose field effective action and discuss two alternative solutions: one corresponding to a Wigner-Weyl realisation of the global symmetry group G in which the vacuum configuration is invariant under G; the other to a mixed realisation in which the vacuum manifold is the coset space G/H = U A(Nf ), where H = Uv(Nf ) is a subgroup of G.

On the superposition of gravitational waves

1975 ◽  
Vol 77 (3) ◽  
pp. 559-565 ◽  
Author(s):  
J. B. Griffiths
Keyword(s):  
Exact Solution ◽  
General Theory ◽  
Gravitational Waves ◽  
Vacuum Field ◽  
Theory Of Relativity ◽  
General Theory Of Relativity ◽  
Field Equations ◽  
Linear Interaction ◽  
Non Linear ◽  
Transverse And Longitudinal Components

AbstractThe nature of the non-linear interaction between two gravitational waves in the general theory of relativity is considered. A new exact solution of the vacuum field equations describing this case is given. It describes two gravitational waves with both transverse and longitudinal components, propagating in opposite directions along ‘shearing’ and ‘twisting’ geodesic congruences with zero contraction

scholarly journals Static plane-symmetric solution of a scalar-tensor theory of gravitation

1983 ◽  
Vol 24 (3) ◽  
pp. 339-342 ◽  
Author(s):  
D. R. K. Reddy ◽  
V. U. M. Rao
Keyword(s):  
Exact Solution ◽  
Symmetric Solution ◽  
Empty Space ◽  
Vacuum Field ◽  
Scalar Tensor Theory ◽  
Field Equations ◽  
Plane Symmetric ◽  
Tensor Theory ◽  
Theory Of Gravitation ◽  
Static Plane

AbstractVacuum field equations in a scalar-tensor theory of gravitation, proposed by Ross, are obtained with the aid of a static plane-symmetric metric. A closed form exact solution to the field equations in this theory is presented which can be considered as an analogue of Taub's empty space-time in Einstein's theory.

scholarly journals Schwarzschild and Kerr solutions of Einstein's field equation: An Introduction

2015 ◽  
Vol 24 (02) ◽  
pp. 1530006 ◽  
Author(s):  
Christian Heinicke ◽  
Friedrich W. Hehl
Keyword(s):  
Gravitational Field ◽  
Field Equation ◽  
Symmetric Solution ◽  
Gravitational Theory ◽  
Vacuum Field ◽  
Kerr Solution ◽  
Spherically Symmetric ◽  
Axially Symmetric ◽  
Schwarzschild Solution ◽  
Spherically Symmetric Solution

Starting from Newton's gravitational theory, we give a general introduction into the spherically symmetric solution of Einstein's vacuum field equation, the Schwarzschild(–Droste) solution, and into one specific stationary axially symmetric solution, the Kerr solution. The Schwarzschild solution is unique and its metric can be interpreted as the exterior gravitational field of a spherically symmetric mass. The Kerr solution is only unique if the multipole moments of its mass and its angular momentum take on prescribed values. Its metric can be interpreted as the exterior gravitational field of a suitably rotating mass distribution. Both solutions describe objects exhibiting an event horizon, a frontier of no return. The corresponding notion of a black hole is explained to some extent. Eventually, we present some generalizations of the Kerr solution.

Sign in / Sign up

Export Citation Format

Share Document