English

Lipschitz geometry and combinatorics of abnormal surface germs

Metric Geometry 2021-08-30 v3 Algebraic Geometry Combinatorics

Abstract

We study outer Lipschitz geometry of real semialgebraic or, more general, definable in a polynomially bounded o-minimal structure over the reals, surface germs. In particular, any definable H\"older triangle is either Lipschitz normally embedded or contains some "abnormal" arcs. We show that abnormal arcs constitute finitely many "abnormal zones" in the space of all arcs, and investigate geometric and combinatorial properties of abnormal surface germs. We establish a strong relation between geometry and combinatorics of abnormal H\"older triangles.

Keywords

Cite

@article{arxiv.2101.02302,
  title  = {Lipschitz geometry and combinatorics of abnormal surface germs},
  author = {Andrei Gabrielov and Emanoel Souza},
  journal= {arXiv preprint arXiv:2101.02302},
  year   = {2021}
}

Comments

58 pages, 14 figures. In Version 3, Examples 2.3, 2.21 and 2.46 added. Fig. 1 illustrating Example 2.21 added. Definition 2.43 of a perfect zone is modified. Lemma 4.7 and Fig. 7 illustrating its proof moved from Section 5 to Section 4. Proofs of Lemma 4.8 and Proposition 4.10 simplified, two figures illustrating previous proofs removed

R2 v1 2026-06-23T21:51:36.107Z