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arXiv · 2204.01985

Mock-integrability and stable solitary vortices

Yukito Koike·Atsushi Nakamula·Akihiro Nishie·Kiori Obuse·Nobuyuki Sawado·Yamato Suda·Kouichi Toda
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Abstract

Localized soliton-like solutions to a $(2+1)$-dimensional hydro-dynamical evolution equation are studied numerically. The equation is so-called Williams-Yamagata-Flierl equation, which governs geostrophic fluid in a certain parameter range. Although the equation does not have an integrable structure in the ordinary sense, we find there exist shape-keeping solutions with very long life in a special background flow and an initial condition. The stability of the localization at the fusion process of two soliton-like objects is also investigated. As for the indicator of the long-term stability of localization, we propose a concept of configurational entropy, which has been introduced in analysis for non-topological solitons in field theories.

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Yukito Koike, Atsushi Nakamula, Akihiro Nishie, Kiori Obuse, Nobuyuki Sawado, Yamato Suda, Kouichi Toda. 2022-04-05. Mock-integrability and stable solitary vortices. https://doi.org/10.1016/j.chaos.2022.112782

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