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Centrifugal Force and Ellipticity behaviour of a slowly rotating ultra compact object

Anshu Gupta·Sai Iyer·A. R. Prasanna
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Abstract

Using the optical reference geometry approach, we have derived in the following, a general expression for the ellipticity of a slowly rotating fluid configuration using Newtonian force balance equation in the conformally projected absolute 3-space, in the realm of general relativity. Further with the help of Hartle-Thorne (H-T) metric for a slowly rotating compact object, we have evaluated the centrifugal force acting on a fluid element and also evaluated the ellipticity and found that the centrifugal reversal occurs at around $R/R_s \approx 1.45$, and the ellipticity maximum at around $R/R_s \approx 2.75$. The result has been compared with that of Chandrasekhar and Miller which was obtained in the full 4-spacetime formalism.

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Anshu Gupta, Sai Iyer, A. R. Prasanna. 1996-03-28. Centrifugal Force and Ellipticity behaviour of a slowly rotating ultra compact object. https://doi.org/10.1088/0264-9381%2F13%2F10%2F007

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