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arXiv · 2405.06351

Energy in critical collapse

Yu Hu·Jun-Qi Guo·Junbin Li·Cheng-Gang Shao·Hongsheng Zhang
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Abstract

We study the energy issue in critical collapse of a spherically symmetric scalar field. It is found that in critical collapse, the contribution from the material energy is greater than that from the gravitational energy. The quantity $m/r$ plays an important role in identifying the formation of apparent horizon in gravitational collapse, where $m$ is the Misner-Sharp mass and $r$ the areal radius. We observe that in critical collapse, the maximum value of $m/r$ fluctuates between $2/15$ and $4/15$. This denotes a large gap between critical collapse and black hole formation for which the criterion is $m/r=1/2$.

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Yu Hu, Jun-Qi Guo, Junbin Li, Cheng-Gang Shao, Hongsheng Zhang. 2024-05-10. Energy in critical collapse. https://doi.org/10.1088/1572-9494/ad0029

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