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arXiv · 2404.03853

A survey of ultra-compact rotating boson star spacetimes

Nikolay Sukhov
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Abstract

Solitonic boson stars (SBS) are compact shell-like objects with an inside having a nearly constant value of scalar field bounded by a thin shell where the scalar field rapidly changes. While the spherically symmetric SBS can be described by an analytical approximation that works well in the thin-shell case, no such approximation exists for rotating SBS and the investigation of such stars poses a numerical challenge. We numerically investigate rotating SBS in case if the relative thickness of the shell is small. We compute Gerosh-Hansen multipole moments to study the structure of SBS spacetime in the outside region and the closeness of SBS to the rotating black hole metric.

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Nikolay Sukhov. 2024-04-05. A survey of ultra-compact rotating boson star spacetimes. https://arxiv.org/abs/2404.03853

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