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arXiv · 0809.4136

Probability for Primordial Black Holes in Multidimensional Universe with Nonlinear Scalar Curvature Terms

B C Paul·A Saha·S Ghose
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Abstract

We investigate multi-dimensional universe with nonlinear scalar curvature terms to evaluate the probability of creation of primordial black holes. For this we obtain Euclidean instanton solution in two different topologies: (a) $S^{D-1}$ - topology which does not accommodate primordial black holes and (b) $S^1\times S^{D-2}$-topology which accommodates a pair of black holes. The probability for quantum creation of an inflationary universe with a pair of black holes has been evaluated assuming a gravitational action which is described by a polynomial function of scalar curvature with or without a cosmological constant ($\Lambda $) using the framework of semiclassical approximation of Hartle-Hawking boundary conditions. We discuss here a class of new gravitational instantons solution in the $R^4$-theory which are relevant for cosmological model building.

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B C Paul, A Saha, S Ghose. 2008-09-24. Probability for Primordial Black Holes in Multidimensional Universe with Nonlinear Scalar Curvature Terms. https://doi.org/10.1103/physrevd.78.084007

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