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arXiv · 1011.2849

Masking a singularity with k-essence fields in an emergent gravity metric

Debashis Gangopadhyay·Sourav Sen Choudhury
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Abstract

It is known that dynamical solutions of the $k$-essence equation of motion change the metric for the perturbations around these solutions and the perturbations propagate in an emergent spacetime with metric $\tilde G^{\mu\nu}$ different from the gravitational metric $g^{\mu\nu}$. We show that for observers travelling with the perturbations, there exist field configurations for the lagrangian $L=[{1\over 2}g^{\mu\nu}\nabla_{\mu}\phi\nabla_{\nu}\phi]^{1\over 2}$ for which a singularity in the gravitational metric $g^{\mu\nu}$ can be masked or hidden for such observers. This is shown for the Schwarzschild and the Reissner-Nordstrom metrics.

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Debashis Gangopadhyay, Sourav Sen Choudhury. 2010-11-12. Masking a singularity with k-essence fields in an emergent gravity metric. https://arxiv.org/abs/1011.2849

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