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arXiv · 1810.04885

Primordial gravastar from inflation

Yu-Tong Wang·Jun Zhang·Yun-Song Piao
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Abstract

The dS bubbles can nucleate spontaneously during inflation, and will be stretched by the cosmological expansion to astrophysical scale. We report on a novel phenomenon that such a bubble might develop into a gravastar (an ultra-compact object with a dS core) after inflation, which witnessed the occurrence of inflation and would survive till today. It is pointed out that if a primordial gravastar was involved in one of the LIGO/Virgo gravitational wave (GW) events, the post-merger object could be a gravastar that will eventually collapse into a black hole. As a result, the late-time GW ringdown waveform will exhibit a series of "echoes" with intervals increasing with time.

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Yu-Tong Wang, Jun Zhang, Yun-Song Piao. 2018-10-11. Primordial gravastar from inflation. https://doi.org/10.1016/j.physletb.2019.06.036

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