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arXiv · 2010.11031

Warping effects in strongly perturbed metrics

Marco Frasca·Riccardo Maria Liberati·Massimiliano Rossi
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Abstract

A technique devised some years ago permits to study a theory in a regime of strong perturbations. This translates into a gradient expansion that, at the leading order, can recover the BKL solution in general relativity. We solve exactly the leading order Einstein equations in a spherical symmetric case, assuming a Schwarzschild metric under the effect of a time-dependent perturbation, and we show that the 4-velocity in such a case is multiplied by an exponential warp factor when the perturbation is properly applied. This factor is always greater than one. We will give a closed form solution of this factor for a simple case. Some numerical examples are also given.

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Marco Frasca, Riccardo Maria Liberati, Massimiliano Rossi. 2020-10-21. Warping effects in strongly perturbed metrics. https://doi.org/10.3390/physics2040039

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