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arXiv · 2512.05574

Two-Point Vortex Confinement in a simply connected domain

Slim Ibrahim·Ruixun Qin·Shengyi Shen
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Abstract

This paper investigates the vortex confinement property of the two-point vortex system in a planar domain. We compute the time over which initial point vortices around a stable stationary point remain within a slightly larger ball. In particular, we show that this concentration persists indefinitely regardless of the vorticity strengths. In the borderline of the stability condition, we show that this time becomes a power law, if in addition, one relaxes the size of the stability ball.

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Slim Ibrahim, Ruixun Qin, Shengyi Shen. 2025-12-05. Two-Point Vortex Confinement in a simply connected domain. https://arxiv.org/abs/2512.05574

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