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Related papers: On certain complex surface singularities

200 papers

In this paper, we first classify singular fibers of proper $C^\infty$ stable maps of 3-dimensional manifolds with boundary into surfaces. Then, we compute the cohomology groups of the associated universal complex of singular fibers, and…

Geometric Topology · Mathematics 2016-07-20 Osamu Saeki , Takahiro Yamamoto

We provide a complete classification of hexagonal singular 3-web germs in the complex plane, satisfying the following two conditions: 1) the Chern connection remains holomorphic at the singular point, 2) the web admits at least one…

Differential Geometry · Mathematics 2012-06-05 Sergey Agafonov

In this paper the singular hypersurfaces in $\mathbb{C}\mathrm{P}^4$ of degree $d$ with an isolated singularity are studied. If the singularity is of type $A_{2k+1}$, under the condition $d<(k+5)/2$, a classification of such hypersurfaces…

Geometric Topology · Mathematics 2007-05-23 Yang Su

We consider fibrations of genus 2 over complex surfaces. The purpose of this paper is primarily to provide a geometric description of the possible structures of the fibration on a neighborhood of a singular fiber. In particular it is shown…

Algebraic Geometry · Mathematics 2012-05-07 Julio C. Rebelo , Bianca Santoro

It was recently proved that for finitely determined germs $ \Phi: ( \mathbb{C}^2, 0) \to ( \mathbb{C}^3, 0) $ the number $C(\Phi)$ of Whitney umbrella points and the number $T(\Phi)$ of triple values of a stable deformation are topological…

Algebraic Topology · Mathematics 2023-01-30 Gergő Pintér , András Sándor

We study groups of germs of complex diffeomorphisms having a property called irreducibility. The notion is motivated by a similar property of the fundamental group of the complement of an irreducible hypersurface in the complex projective…

Dynamical Systems · Mathematics 2019-04-18 V. León , M. Martelo , B. Scárdua

We consider a semistable degeneration of K3 surfaces, equipped with an effective divisor that defines a polarisation of degree two on a general fibre. We show that the map to the relative log canonical model of the degeneration maps every…

Algebraic Geometry · Mathematics 2013-12-09 Alan Thompson

For a germ of a variety $\mathcal{V}, 0 \subset \mathbb C^N, 0$, a singularity $\mathcal{V}_0$ of type $\mathcal{V}$, is given by a germ $f_0 : \mathbb C^n, 0 \to \mathbb C^N, 0$ which is transverse to $\mathcal{V}$ in an appropriate sense…

Algebraic Geometry · Mathematics 2019-11-07 James Damon

Let $(X, 0)$ be a complex analytic surface germ embedded in $(\mathbb{C}^n,0)$ with an isolated singularity and $\Phi=(g,f):(X,0) \longrightarrow (\mathbb{C}^2,0)$ be a finite morphism. We define a family of analytic invariants of the…

Algebraic Geometry · Mathematics 2024-03-12 Yenni Cherik

We give a survey on some aspects of the topological investigation of isolated singularities of complex hypersurfaces by means of Picard-Lefschetz theory. We focus on the concept of distinguished bases of vanishing cycles and the concept of…

Algebraic Geometry · Mathematics 2019-05-30 Wolfgang Ebeling

In this work, we study families of singular surfaces in $\mathbb{C}^3$ parametrized by $\mathcal{A}$-finitely determined map germs. We consider the topological triviality and Whitney equisingularity of an unfolding $F$ of a finitely…

Complex Variables · Mathematics 2017-03-16 M. A. S. Ruas , O. N. Silva

We study the nilpotent part $N'$ of a pseudo-periodic automorphism $h$ of a real oriented surface with boundary $\Sigma$. We associate a quadratic form $Q$ defined on the first homology group (relative to the boundary) of the surface…

We show that the topological equivalence class of holomorphic foliation germs with an isolated singularity of Poincar\'e type is determined by the topological equivalence class of the real intersection foliation of the (suitably normalized)…

Complex Variables · Mathematics 2017-07-20 Thomas Eckl , Michael Lönne

We study the boundary L_t of the Milnor fiber for the non-isolated singularities in C^3 with equation z^m - g(x,y) = 0 where g(x,y) is a non-reduced plane curve germ. We give a complete proof that L_t is a Waldhausen graph manifold and we…

Algebraic Geometry · Mathematics 2007-05-23 Francoise Michel , Anne Pichon , Claude Weber

Suppose that $f$ defines a singular, complex affine hypersurface. If the critical locus of $f$ is one-dimensional, we obtain new general bounds on the ranks of the homology groups of the Milnor fiber of $f$. This result has an interesting…

Algebraic Geometry · Mathematics 2007-05-23 Lê Dũng Tráng , David B. Massey

We prove a formula for the polar degree of projective hypersurfaces in terms of the Milnor data of the singularities, extending to 1-dimensional singularities the Dimca-Papadima result for isolated singularities. We discuss the…

Algebraic Geometry · Mathematics 2022-05-18 Dirk Siersma , Mihai Tibăr

We consider germs of holomorphic vector fields with an isolated singularity at the origin $0\in\mathbb{C}^2$. We introduce a notion of stability, similar to "Lyapunov stability". For such a germ, called $L$-stable singularity, either the…

Dynamical Systems · Mathematics 2016-01-29 Victor Leon , Bruno Scardua

We study the classification of singularities of holomorphic foliations and non-integrable one-forms under the hypothesis of transversality with real hypersurfaces.

Complex Variables · Mathematics 2010-12-15 Toshikazu Ito , Bruno Scardua

The article starts with some introductory material about resolution graphs of normal surface singularities (definitions, topological/homological properties, etc). We then discuss the case when the normal surface singularity is an N-fold…

Algebraic Geometry · Mathematics 2009-09-25 András Némethi

In this article we apply the results in the article "On Isolated Real Singularities I" to the study of real $ADE$-singularities. We show that said results enables us to find the homology groups of the Milnor fibres of real…

Algebraic Geometry · Mathematics 2021-10-12 Lars Andersen