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arXiv · 1612.07455

Geodesic Flows in a Charged Black Hole Spacetime with Quintessence

Hemwati Nandan·Rashmi Uniyal
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Abstract

We investigate the evolution of timelike geodesic congruences, in the background of a charged black hole spacetime surrounded with quintessence. The Raychaudhuri equations for three kinematical quantities namely the expansion scalar, shear and rotation along the geodesic flows in such spacetime are obtained and solved numerically. We have also analysed both the weak and the strong energy conditions for the focusing of timelike geodesic congruences. The effect of the normalisation constant and equation of state parameter on the evolution of the expansion scalar is discussed, for the congruences with and without an initial shear and rotation. It is observed that there always exists a critical value of the initial expansion below which we have focusing with smaller values of the normalisation constant and equation of state parameter. As the corresponding values of both of these parameters are increased, no geodesic focusing is observed. The results obtained are then compared with those of the Reissener Nordtrom and Schwarzschild black hole spacetimes as well as their de-Sitter black hole analouges accordingly.

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Hemwati Nandan, Rashmi Uniyal. 2016-12-22. Geodesic Flows in a Charged Black Hole Spacetime with Quintessence. https://arxiv.org/abs/1612.07455

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