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arXiv · 2109.04162

A semi-tetrad decomposition of the Kerr spacetime

Chevarra Hansraj·Rituparno Goswami·Sunil D. Maharaj
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Abstract

In this paper we perform a semi-tetrad decomposition of the Kerr spacetime. We apply the 1+1+2 covariant method to the Kerr spacetime in order to describe its geometry outside the ergoregion. As a result we are able to explicitly write down the 1+1+2 Kerr quantities, and the evolution and propagation equations they satisfy. This formalism allows us to present the kinematic and dynamic quantities in a transparent geometrical manner; and also to highlight the role of vorticity. To our knowledge, using the 1+1+2 formalism to investigate the Kerr spacetime is a novel approach and this provides new insights into the spacetime geometry in an easier manner than alternate approaches. Furthermore we make corrections to earlier equations in the 1+1+2 formalism applied to the Kerr spacetime.

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Chevarra Hansraj, Rituparno Goswami, Sunil D. Maharaj. 2021-09-09. A semi-tetrad decomposition of the Kerr spacetime. https://doi.org/10.1140/epjc/s10052-023-11433-x

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