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| In this talk, traveling spots observed in two-dimensional excitable media are explored. First, we introduce the singular limit problem of the FitzHugh-Nagumo equations. Then we show the existence of the traveling spot including the front and the back. Using this traveling spots, I will explain some mathematical understanding of the formation of spirals which is induced by obstacles. The formation of the spirals depends on the shapes of the obstacle. This spiral formation is deeply related to the ventricular fibrillation. |
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