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arXiv · 2108.04365

Kurdyka-{\L}ojasiewicz functions and mapping cylinder neighborhoods

Florentiu Daniel Cibotaru·Fernando Galaz-Garcia
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Abstract

Kurdyka-{\L}ojasiewicz (K{\L}) functions are real-valued functions characterized by a differential inequality involving the norm of their gradient. This class of functions is quite rich, containing objects as diverse as subanalytic, transnormal or Morse functions. We prove that the zero locus of a Kurdyka-{\L}ojasiewicz function admits a mapping cylinder neighborhood. This implies, in particular, that wildly embedded topological 2-manifolds in 3-dimensional Euclidean space, such as Alexander horned spheres, do not arise as the zero loci of K{\L} functions.

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Florentiu Daniel Cibotaru, Fernando Galaz-Garcia. 2021-08-09. Kurdyka-{\L}ojasiewicz functions and mapping cylinder neighborhoods. https://arxiv.org/abs/2108.04365

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