Charged gravastars admitting conformal motion
Abstract
We propose a new model of a gravastar admitting conformal motion. While retaining the framework of the Mazur-Mottola model, the gravastar is assumed to be internally charged, with an exterior defined by a Reissner-Nordström instead of a Schwarzschild line element. The solutions, obtained by exploiting an assumed conformal Killing vector, involve (i) the interior region, (ii) the shell, and (iii) the exterior region of the sphere. Of these three cases the first one is of primary interest since the total gravitational mass here turns out to be an electromagnetic mass under some specific conditions. This suggests that the interior de Sitter vacuum of a charged gravastar is essentially an electromagnetic mass model that must generate gravitational mass which provides a stable configuration by balancing the repulsive pressure arising from charge with its attractive gravity to avert a singularity. Therefore the present model, like the Mazur-Mottola model, results in the construction of a compact astrophysical object, as an alternative to a black hole. We have also analyzed various other aspects such as the stress energy tensor in the thin shell and the entropy of the system.
- Publication:
-
Physics Letters B
- Pub Date:
- July 2011
- DOI:
- 10.1016/j.physletb.2011.06.001
- arXiv:
- arXiv:1012.5605
- Bibcode:
- 2011PhLB..701..388U
- Keywords:
-
- General Relativity and Quantum Cosmology
- E-Print:
- Minor addition, Accepted in Phys. Lett. B