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arXiv · 2406.17122

Faster computation of Whitney stratifications and their minimization

Martin Helmer·Rafael Mohr
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Abstract

We describe two new algorithms for the computation of Whitney stratifications of real and complex algebraic varieties. The first algorithm is a modification of the algorithm of Helmer and Nanda (HN), but is made more efficient by using techniques for equidimensional decomposition rather than computing the set of associated primes of a polynomial ideal at a key step in the HN algorithm. We note that this modified algorithm may fail to produce a minimal Whitney stratification even when the HN algorithm would produce a minimal stratification. The second algorithm coarsens a given Whitney stratification of a complex variety to the unique minimal Whitney stratification; we refer to this as the minimization of a stratification. The theoretical basis for our approach is a classical result of Teissier. To our knowledge this yields the first algorithm for computing a minimal Whitney stratification.

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Martin Helmer, Rafael Mohr. 2025-11-27. Faster computation of Whitney stratifications and their minimization. https://arxiv.org/abs/2406.17122

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