The geometry of bi-Perron numbers with real or unimodular Galois conjugates

Livio Liechti; Joshua Pankau

doi:10.1093/imrn/rnab235

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arXiv · 2009.03647

The geometry of bi-Perron numbers with real or unimodular Galois conjugates

Livio Liechti·Joshua Pankau

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Abstract

Among all bi-Perron numbers, we characterise those all of whose Galois conjugates are real or unimodular as the ones that admit a power which is the stretch factor of a pseudo-Anosov homeomorphism arising from Thurston's construction. This is in turn equivalent to admitting a power which is the spectral radius of a bipartite Coxeter transformation.

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Livio Liechti, Joshua Pankau. 2020-09-08. The geometry of bi-Perron numbers with real or unimodular Galois conjugates. https://doi.org/10.1093/imrn%2Frnab235

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