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Singularities in Low Energy $d = 4$ Heterotic String and Brans-Dicke Theories

S. Kalyana Rama
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Abstract

We present the static, spherically symmetric solutions of the low energy $d = 4$ string. They form a simple generalisation of the Schwarzschild solution and describe the gravitational field of a spherical star in perturbative string theory. If the Robertson parameter $γ$ is different from one, these solutions describe singular objects with naked singularities at their horizons, and whose Hawking temperature is infinite. These objects might represent ``massive remnants'', the end states of black holes. Our analysis also implies that Brans-Dicke theory has a naked singularity. Invoking cosmic censorship conjecture will rule out Brans-Dicke theory.

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S. Kalyana Rama. 1993-10-10. Singularities in Low Energy $d = 4$ Heterotic String and Brans-Dicke Theories. https://arxiv.org/abs/hep-th/9309046

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