English

Conjectures on stably Newton degenerate singularities

Algebraic Geometry 2020-12-25 v3

Abstract

We discuss a problem of Arnold, whether every function is stably equivalent to one which is non-degenerate for its Newton diagram. We argue that the answer is negative. We describe a method to make functions non-degenerate after stabilisation and give examples of singularities where this method does not work. We conjecture that they are in fact stably degenerate, that is not stably equivalent to non-degenerate functions. We review the various non-degeneracy concepts in the literature. For finite characteristic we conjecture that there are nowild vanishing cycles for non-degenerate singularities. This implies that the simplest example of singularities with finite Milnor number, xp+xqx^p+x^q in characteristic pp, is not stably equivalent to a non-degenerate function. We argue that irreducible plane curves with an arbitrary number of Puiseux pairs (in characteristic zero) are stably non-degenerate. As the stabilisation involves many variables, it becomes very difficult to determine the Newton diagram in general, but the form of the equations indicates that the defining functions are non-degenerate.

Keywords

Cite

@article{arxiv.1406.0328,
  title  = {Conjectures on stably Newton degenerate singularities},
  author = {Jan Stevens},
  journal= {arXiv preprint arXiv:1406.0328},
  year   = {2020}
}

Comments

This is a completely rewritten version, with new title, more details on non-degenaracy conditions and more examples

R2 v1 2026-06-22T04:28:17.997Z