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arXiv · 2110.15512

Spin conservation of cosmic filaments

Ming-Jie Sheng·Sijia Li·Hao-Ran Yu·Wei Wang·Peng Wang·Xi Kang
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Abstract

Cosmic filaments are the largest collapsing structure in the Universe. Recently both observations and simulations inferred that cosmic filaments have coherent angular momenta (spins). Here we use filament finders to identify the filamentary structures in cosmological simulations and study their physical origins, which are well described by the primordial tidal torque of their Lagrangian counterpart regions -- protofilaments. This initial angular momenta statistically preserve their directions to low redshifts. We further show that a spin reconstruction method can predict the spins of filaments and potentially relate their spins to the initial conditions of the Universe. This correlation provides a new way of constraining and obtaining additional information of the initial perturbations of the Universe.

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Ming-Jie Sheng, Sijia Li, Hao-Ran Yu, Wei Wang, Peng Wang, Xi Kang. 2021-10-29. Spin conservation of cosmic filaments. https://doi.org/10.1103/physrevd.105.063540

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