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arXiv · 2105.11406

Sufficiently dense Kuramoto networks are globally synchronizing

Abstract

Consider any network of $n$ identical Kuramoto oscillators in which each oscillator is coupled bidirectionally with unit strength to at least $μ(n-1)$ other oscillators. There is a critical value of the connectivity, $μ_c$, such that whenever $μ>μ_c$, the system is guaranteed to converge to the all-in-phase synchronous state for almost all initial conditions, but when $μ<μ_c$, there are networks with other stable states. The precise value of the critical connectivity remains unknown, but it has been conjectured to be $μ_c=0.75$. In 2020, Lu and Steinerberger proved that $μ_c\leq 0.7889$, and Yoneda, Tatsukawa, and Teramae proved in 2021 that $μ_c > 0.6838$. In this paper, we prove that $μ_c\leq 0.75$ and explain why this is the best upper bound that one can obtain by a purely linear stability analysis.

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Martin Kassabov, Steven H. Strogatz, Alex Townsend. 2021-05-24. Sufficiently dense Kuramoto networks are globally synchronizing. https://doi.org/10.1063/5.0057659

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