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arXiv · 1005.1839

Some planar isospectral domains

Peter Buser·John Conway·Peter Doyle·Klaus-Dieter Semmler
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Abstract

We give a number of examples of isospectral pairs of plane domains, and a particularly simple method of proving isospectrality. One of our examples is a pair of domains that are not only isospectral but homophonic: Each domain has a distinguished point such that corresponding normalized Dirichlet eigenfunctions take equal values at the distinguished points. This shows that one really can't hear the shape of a drum.

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Peter Buser, John Conway, Peter Doyle, Klaus-Dieter Semmler. 2010-05-11. Some planar isospectral domains. https://arxiv.org/abs/1005.1839

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