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arXiv · 2402.05093

Moduli Parameters of Complex Singularities with Non-Degenerate Newton Boundary

Janko Boehm·Magdaleen S. Marais·Gerhard Pfister
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Abstract

Our recent extension of Arnold's classification includes all singularities of corank up to two equivalent to a germ with a non-degenerate Newton boundary, thus broadening the classification's scope significantly by a class which is unbounded with respect to modality and Milnor number. This method is based on proving that all right-equivalence classes within a mu-constant stratum can be represented by a single normal form derived from a regular basis of a suitably selected special fiber. While both Arnold's and our preceding work on normal forms addresses the determination of a normal form family containing the given germ, this paper takes the next natural step: We present an algorithm for computing for a given germ the values of the moduli parameters in its normal form family, that is, a normal form equation in its stable equivalence class. This algorithm will be crucial for understanding the moduli stacks of such singularities. The implementation of this algorithm, along with the foundational classification techniques, is implemented in the library arnold.lib for the computer algebra system Singular.

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Janko Boehm, Magdaleen S. Marais, Gerhard Pfister. 2024-02-07. Moduli Parameters of Complex Singularities with Non-Degenerate Newton Boundary. https://arxiv.org/abs/2402.05093

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