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arXiv · 0908.0197

Deformation of a self-propelled domain in an excitable reaction-diffusion system

Takao Ohta·Takahiro Ohkuma·Kyohei Shitara
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Abstract

We formulate the theory for a self-propelled domain in an excitable reaction-diffusion system in two dimensions where the domain deforms from a circular shape when the propagation velocity is increased. In the singular limit where the width of the domain boundary is infinitesimally thin, we derive a set of equations of motion for the center of gravity and two fundamental deformation modes. The deformed shapes of a steadily propagating domain are obtained. The set of time-evolution equations exhibits a bifurcation from a straight motion to a circular motion by changing the system parameters.

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Takao Ohta, Takahiro Ohkuma, Kyohei Shitara. 2009-08-03. Deformation of a self-propelled domain in an excitable reaction-diffusion system. https://doi.org/10.1103/physreve.80.056203

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