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arXiv · 2103.01522

Dynamical Evolution of Voids with Surrounding Gravitational Tidal Field

Mutsumi Minoguchi·Atsushi J. Nishizawa·Tsutomu T. Takeuchi·Naoshi Sugiyama
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Abstract

The void ellipticity distribution today can be well explained by the tidal field. Going a step further from the overall distribution, we investigate individuality on the tidal response of void shape in non-linear dynamical evolution. We perform an N-body simulation and trace individual voids using particle ID. The voids are defined based on Voronoi tessellation and watershed algorithm, using public code VIDE. A positive correlation is found between the time variation of void ellipticity and tidal field around a void if the void maintains its constituent particles. Such voids tend to have smaller mass densities. Conversely, not a few voids significantly deform by particle exchange, rather than the tidal field. Those voids may prevent us from correctly proving a quadrupole field of gravity out of a void shape.

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Mutsumi Minoguchi, Atsushi J. Nishizawa, Tsutomu T. Takeuchi, Naoshi Sugiyama. 2021-03-02. Dynamical Evolution of Voids with Surrounding Gravitational Tidal Field. https://doi.org/10.1093/mnras%2Fstab631

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