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arXiv · 1106.2054

Gravitational collapse of K-essence Matter in Painlev\'{e}-Gullstrand coordinates

C. Danielle Leonard·Jonathan Ziprick·Gabor Kunstatter·Robert B. Mann
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Abstract

We conduct numerical simulations in Painlev\'{e}-Gullstrand coordinates of a variety of K-essence-type scalar fields under spherically symmetric gravitational collapse. We write down generic conditions on the K-essence lagrangian that can be used to determine whether superluminality and Cauchy breakdown are possible. Consistent with these conditions, for specific choices of K-essence-type fields we verify the presence of superluminality during collapse, while for other type we do not. We also demonstrate that certain choices of K-essence scalar fields present issues under gravitational collapse in Painlev\'{e}-Gullstrand coordinates, such as a breakdown of the Cauchy problem.

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C. Danielle Leonard, Jonathan Ziprick, Gabor Kunstatter, Robert B. Mann. 2011-06-10. Gravitational collapse of K-essence Matter in Painlev\'{e}-Gullstrand coordinates. https://doi.org/10.1007/jhep10(2011)028

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