On Teissier's example of an equisingularity class that cannot be defined over the rationals

Adam Parusiński; Laurentiu Paunescu

doi:10.4064/1p241208-25-4

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arXiv · 2501.10863

On Teissier's example of an equisingularity class that cannot be defined over the rationals

Adam Parusiński·Laurentiu Paunescu

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Abstract

A result of Teissier says that the cone over one of classical polygon examples in the real projective space gives, by complexification, a surface singularity which is not Whitney equisingular to a singularity defined over the field of rational numbers Q. In this note we correct the example and give a complete proof of Tesissier's result.

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Adam Parusiński, Laurentiu Paunescu. 2026-02-02. On Teissier's example of an equisingularity class that cannot be defined over the rationals. https://doi.org/10.4064/1p241208-25-4

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