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arXiv · 1908.08751

Threaded rings that swim in excitable media

Abstract

Cardiac tissue and the Belousov-Zhabotinsky reaction provide two notable examples of excitable media that support scroll waves, in which a filament core is the source of spiral waves of excitation. Here we consider a novel topological configuration in which a closed filament loop, known as a scroll ring, is threaded by a pair of counter-rotating filaments that are perpendicular to the plane of the ring and end on the boundary of a thin medium. We simulate the dynamics of this threaded ring (thring) in the photosensitive Belousov-Zhabotinsky excitable medium, using the modified Oregonator reaction-diffusion equations. These computations reveal that the threading topology induces an exotic motion in which the thring swims in the plane of the ring. We propose a light templating protocol to create a thring in the photosensitive Belousov-Zhabotinsky medium and provide experimental confirmation that this protocol indeed yields a thring.

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BibTeXRIS

Antonio Cincotti, Fabian Maucher, David Evans, Brette M. Chapin, Kate Horner, Elizabeth Bromley, Andrew Lobb, Jonathan W. Steed, Paul Sutcliffe. 2019-11-08. Threaded rings that swim in excitable media. https://doi.org/10.1103/physrevlett.123.258102

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