K S Virbhadra
Articles written in Pramana – Journal of Physics
Volume 33 Issue 4 October 1989 pp 449-454 Relativity
Spin precession of a charged particle in a uniform magnetic field on a static space-time
We investigate the ratio of spin precession frequency to orbital frequency for a spinning charged particle confined to circular orbit in the equatorial plane of a compact object, with a uniform magnetic field, as described by the Wald and the Ernst potentials. In order to see the difference in behaviours for particles with different
Volume 38 Issue 1 January 1992 pp 31-35
Energy and momentum in Vaidya spacetime
The components of the energy-momentum pseudotensors of Einstein, Tolman, Landau and Lifshitz, and Møller are evaluated for the Vaidya radiating spacetime. These pseudotensors are found to be traceless for this spacetime. The pseudotensors of Einstein and Tolman give exactly same result for all their components. Unlike in the case of the Kerr-Newman field, the pseudotensor of Møller gives the same energy as given by that of the Einstein, Tolman or Landau and Lifshitz.
Volume 40 Issue 4 April 1993 pp 273-275
Gravitational field of a tachyon in a de Sitter universe
An exact solution of Einstein’s equations is interpreted as describing the gravitational field of a tachyon in a de Sitter universe. Switching off the cosmological constant yields the gravitational field of a tachyon in flat spacetime background.
Volume 44 Issue 4 April 1995 pp 317-322
Exact solutions of Einstein and Einstein-scalar equations in 2 + 1 dimensions
A nonstatic and circularly symmetric exact solution of the Einstein equations (with a cosmological constant Λ and null fluid) in 2 + 1 dimensions is given. This is a nonstatic generalization of the uncharged spinless BTZ metric. For Λ = 0, the spacetime is though not flat, the Kretschmann invariant vanishes. The energy, momentum, and power output for this metric are obtained. Further a static and circularly symmetric exact solution of the Einsteinmassless scalar equations is given, which has a curvature singularity at
Volume 45 Issue 2 August 1995 pp 175-179
Gravitational and electromagnetic fields of a charged tachyon
An axially symmetric exact solution of the Einstein-Maxwell equations is obtained and is interpreted to give the gravitational and electromagnetic fields of a charged tachyon. Switching off the charge parameter yields the solution for the uncharged tachyon which was earlier obtained by Vaidya. The null surfaces for the charged tachyon are discussed.
Volume 45 Issue 2 August 1995 pp 181-187
We give a non-static exact solution of the Einstein-Maxwell equations (with null fluid), which is a non-static magnetic charge generalization to the Bonnor-Vaidya solution and describes the gravitational and electromagnetic fields of a non-rotating massive radiating dyon. In addition, using the energy-momentum pseudotensors of Einstein and Landau and Lifshitz we obtain the energy, momentum, and power output of the radiating dyon and find that both prescriptions give the same result.
Volume 45 Issue 2 August 1995 pp 215-219 Brief Report
Energy and momentum of cylindrical gravitational waves-II
Recently Rosen and the present author obtained the energy and momentum densities of cylindrical gravitational waves in Einstein’s prescription and found them to be finite and reasonable. In the present paper we calculate the same in the prescriptions of Tolman as well as Landau and Lifshitz and discuss the results.
Volume 94, 2020
All articles
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode
© 2017-2019 Indian Academy of Sciences, Bengaluru.