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Short Distance Repulsive Gravity as a Consequence of Non Trivial PPN Parameters $β$ and $γ$

S. Kalyana Rama·Sasanka Ghosh
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Abstract

We look for a graviton-dilaton theory which can predict non trivial values of the PPN parameters $β$ and/or $γ$ for a charge neutral point star, without any naked singularity. With the potential for dilaton $ϕ$ set to zero, it contains one arbitrary function $ψ(ϕ)$. Our requirements impose certain constraints on $ψ$, which lead to the following generic and model independent novel results: For a charge neutral point star, the gravitational force becomes repulsive at distances of the order of, but greater than, the Schwarzschild radius $r_0$. There is also no horizon for $r > r_0$. These results suggest that black holes are unlikely to form in a stellar collapse in this theory.

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S. Kalyana Rama, Sasanka Ghosh. 1996-07-05. Short Distance Repulsive Gravity as a Consequence of Non Trivial PPN Parameters $β$ and $γ$. https://doi.org/10.1016/0370-2693(96)00818-0

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