Hearing the shape of a triangle

Daniel Grieser; Svenja Maronna

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arXiv · 1208.3163

Hearing the shape of a triangle

Daniel Grieser·Svenja Maronna

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Abstract

In 1966 Mark Kac asked the famous question 'Can one hear the shape of a drum?'. While this was later shown to be false in general, it was proved by C. Durso that one can hear the shape of a triangle. After an introduction to the general inverse spectral problem we will give a new proof of this fact. The central point of the argument is to show that area, perimeter and the sum of the reciprocals of the angles determine a triangle uniquely. This is proved using convexity arguments and the partial fraction expansion of $\sin^{-2}x$.

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Daniel Grieser, Svenja Maronna. 2012-08-15. Hearing the shape of a triangle. https://arxiv.org/abs/1208.3163

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