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Related papers: Lipschitz Geometry of Real Semialgebraic Surfaces

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We give conditions for topological and bi-Lipschitz equivalences within a class of mixed singularities of Pham-Brieskorn type. As a consequence, we construct infinite families that are topologically trivial but have distinct bi-Lipschitz…

Algebraic Geometry · Mathematics 2026-05-05 Inácio Rabelo

In this paper, we prove that two normal complex surface germs that are inner bilipschitz--but not necessarily orientation-preserving--homeomorphic, have in fact the same oriented topological type and the same minimal plumbing graph. Along…

Algebraic Geometry · Mathematics 2025-11-10 Lorenzo Fantini , Anne Pichon

A normal pair of H\"older triangles is the union of two normally embedded H\"older triangles satisfying some natural conditions on the tangency orders of their boundary arcs. It is a special case of a surface germ, a germ at the origin of a…

Metric Geometry · Mathematics 2024-12-19 Lev Birbrair , Andrei Gabrielov

We investigate the (ambient) bi-Lipschitz V-equivalence of two-variable mixed polynomials satisfying the Newton inner non-degeneracy condition. Concerning triviality, we show that ambient bi-Lipschitz V-triviality for families $\{f +…

Metric Geometry · Mathematics 2025-12-02 Davi Lopes Medeiros , José Edson Sampaio , Eder Leandro Sanchez Quiceno

An explanation is given for the initially surprising ubiquity of separating sets in normal complex surface germs. It is shown that they are quite common in higher dimensions too. The relationship between separating sets and the geometry of…

Algebraic Geometry · Mathematics 2011-07-29 Lev Birbrair , Alexandre Fernandes , Walter D Neumann

In this paper, we introduce the notion of local quasi-isometry for metric germs and prove that two definable germs are quasi-isometric if and only if their tangent cones are bi-Lipschitz homeomorphic. Since bi-Lipschitz equivalence is a…

Algebraic Geometry · Mathematics 2023-05-26 Nhan Nguyen

It is known by a result of Mendes and Sampaio that the Lipschitz normal embedding of a subanalytic germ is fully characterized by the Lipschitz normal embedding of its link. In this note, we show that the result still holds for definable…

Geometric Topology · Mathematics 2022-03-02 Nhan Nguyen

The main result states that a connected conic singular sub-manifold of a Riemannian manifold, compact when the ambient manifold is non-Euclidean, is Lipschitz Normally Embedded: the outer and inner metric space structures are metrically…

Differential Geometry · Mathematics 2023-06-27 André Costa , Vincent Grandjean , Maria Michalska

We study invariance of multiplicity of complex analytic germs and degree of complex affine sets under outer bi-Lipschitz transformations (outer bi-Lipschitz homeomorphims of germs in the first case and outer bi-Lipschitz homeomorphims at…

Algebraic Geometry · Mathematics 2018-09-05 Javier Fernández de Bobadilla , Alexandre Fernandes , J. Edson Sampaio

We introduce a sectional criterion for testing if complex analytic germs $(X,0) \subset (\bC^n, 0)$ are Lipschitz non normally embedded.

Complex Variables · Mathematics 2020-01-06 Maciej Denkowski , Mihai Tibar

We investigate the classification of quasihomogeneous polynomials in two variables with real coefficients under semialgebraic bi-Lipschitz equivalence in a neighborhood of the origin in ${\mathbb R}^2$. Building on the work of Birbrair,…

Algebraic Geometry · Mathematics 2025-03-11 Sergio Alvarez

The main result of the paper states that a connected complex affine algebraic curve is Lipschitz normally embedded (shortened to LNE afterwards) in $\mathbb{C}^n$ if and only if its germ at any singular point is a finite union of…

Algebraic Geometry · Mathematics 2023-11-28 André Costa , Vincent Grandjean , Maria Michalska

The Moderately Discontinuous Homology (MD-Homology, for short) was created recently in 2022 by Fern\'andez de Bobadilla at al. and it captures deep Lipschitz phenomena. However, to become a definitive powerful tool, it must be widely…

Metric Geometry · Mathematics 2024-08-05 Davi Lopes Medeiros , José Edson Sampaio , Emanoel Souza

In this article, we prove that for a definable set in an o-minimal structure with connected link (at 0 or infinity), the inner distance of the link is equivalent to the inner distance of the set restricted to the link. With this result, we…

Metric Geometry · Mathematics 2024-03-05 José Edson Sampaio

We investigate connections between Lipschitz geometry of real algebraic varieties and properties of their arc spaces. For this purpose we develop motivic integration in the real algebraic set-up. We construct a motivic measure on the space…

Algebraic Geometry · Mathematics 2020-10-22 Jean-Baptiste Campesato , Toshizumi Fukui , Krzysztof Kurdyka , Adam Parusinski

This paper is devoted to the study of the LNE property in complex analytic hypersurface parametrized germs, that is, the sets that are images of finite analytic map germs from $(\mathbb{C}^n,0)$ to $(\mathbb{C}^{n+1},0)$. We prove that if…

We classify germs at the origin of real analytic Lorentz metrics on R^3 which are quasihomogeneous, in the sense that they are locally homogeneous on an open set containing the origin in its closure, but not locally homogeneous in the…

Differential Geometry · Mathematics 2014-01-27 Sorin Dumitrescu

We produce examples of complex algebraic surfaces with isolated singularities such that these singularities are not metrically conic, i.e. the germs of the surfaces near singular points are not bi-Lipschitz equivalent, with respect to the…

Algebraic Geometry · Mathematics 2007-05-23 Lev Birbrair , Alexandre Fernandes

We present a complete classification of complex plane algebraic curves, equipped with the induced Euclidean, up to global bilipschitz homeomorphism.

Algebraic Geometry · Mathematics 2020-03-17 Renato Targino

In the article we give a self-contained new proof that a normal quasi-ordinary surface germ is analytically isomorphic to a cyclic quotient surface germ.

Algebraic Geometry · Mathematics 2024-10-29 Françoise Michel , Claude Weber