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arXiv · 1801.04626

On a discriminant knot group problem of Brieskorn

Michael Lönne
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Abstract

Quite some time ago, at the singularity conference at Carg\`ese 1972 Brieskorn asked the following question: Is the local fundamental group $\pi_1^{s}(S-D)$ of the discriminant complement inside the semi-universal unfolding $S$ of an isolated hypersurface singularity constant for $s$ in the $\mu$-constant stratum $\Sigma_E$? We review this question and give an affirmative answer in case of singular plane curve germs of multiplicity at most $3$.

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Michael Lönne. 2018-01-15. On a discriminant knot group problem of Brieskorn. https://arxiv.org/abs/1801.04626

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