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Related papers: Homotopy Type of Disentanglements of Multi-germs

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We consider the possible disentanglements of holomorphic map germs $f \colon (\mathbb C^n,0) \to (\mathbb C^N,0)$, $n < N$, with nonisolated locus of instability $\operatorname{Inst}(f)$. The aim is to achieve lower bounds for their…

Algebraic Geometry · Mathematics 2019-12-13 Matthias Zach , Guillermo Peñafort Sanchis

We describe a new algebro-geometric perspective on the study of the Milnor fibration and, as a first step toward putting it into practice, prove powerful criteria for a deformation of a holomorphic function germ to admit a stratification on…

Algebraic Geometry · Mathematics 2025-03-04 Alex Hof

We use topology of configuration spaces to give a characterization of Neuwirth--Stallings pairs $(S^5, K)$ with $\dim K = 2$. As a consequence, we construct polynomial map germs $(\mathbb{R}^{6},0)\to (\mathbb{R}^{3},0)$ with an isolated…

Geometric Topology · Mathematics 2016-05-06 R. Araújo Dos Santos , M. A. B. Hohlenwerger , O. Saeki , T. O. Souza

We study the structure of classical groups of equivalences for smooth multigerms $f \colon (N,S) \to (P,y)$, and extend several known results for monogerm equivalences to the case of mulitgerms. In particular, we study the group $\A$ of…

Differential Geometry · Mathematics 2011-10-11 Aasa Feragen , Andrew du Plessis

Let f and g be holomorphic function-germs vanishing at the origin of a complex analytic germ of dimension three. Suppose that they have no common irreducible component and that the real analytic map-germ given by the multiplication of f by…

Algebraic Geometry · Mathematics 2013-04-02 Javier Fernandez de Bobadilla , Aurelio Menegon Neto

In the study of equisingularity of families of mappings Gaffney introduced the crucial notion of excellent unfoldings. This definition essentially says that the family can be stratified so that there are no strata of dimension 1 other than…

Algebraic Geometry · Mathematics 2008-07-03 Kevin Houston

We describe a canonical procedure for associating to any (germ of) holomorphic self-map f of C^n fixing the origin such that df_O is invertible and non-diagonalizable an n-dimensional complex manifold M, a holomorphic map p from M to C^n, a…

Complex Variables · Mathematics 2007-05-23 Marco Abate

We prove fibration theorems \`a la Milnor for differentiable real maps with non isolated critical values. We study the situation for maps with linear discriminant, and prove that the concept of d-regularity is the key point for the…

Algebraic Geometry · Mathematics 2020-02-18 JosÉ Luis Cisneros-Molina , AurÉlio Menegon , JosÉ Seade , Jawad Snoussi

Let M be a smooth connected compact surface, P be either the real line R^1 or the circle S^1, and f:M-->P be a smooth mapping. In a previous series of papers for the case when f is a Morse map the author calculated the homotopy types of…

Geometric Topology · Mathematics 2009-12-17 Sergiy Maksymenko

We study the monodromy of vanishing cycles for map-germs $f:(C^{2n},0) \to (\CM^k,0)$ whose components are in involution. Although the singular fibres of such maps have non-isolated singularities, it is shown that the regular fibres are…

Algebraic Geometry · Mathematics 2007-05-23 Mauricio D. Garay

We construct all codimension 1 multi-germs of maps (k^n,T)-->(k^p,0) with n > p-2, (n,p) nice dimensions, k = R or C, by augmentation and concetenation operations, starting from mon-germs (|T|=1). As an application, we prove general results…

Algebraic Geometry · Mathematics 2007-05-23 Thomas Cooper , David Mond , Roberta Wik Atique

Let $f\colon (\mathbb C^n,S)\to (\mathbb C^p,0)$ be a finite map-germ with $n<p$ and $Y_\delta$ the image of a small perturbation $f_\delta$. We show that the reduced cohomology of $Y_\delta$ is concentrated in a range of degrees determined…

Algebraic Geometry · Mathematics 2021-03-30 Yongqiang Liu , Guillermo Peñafort Sanchis , Matthias Zach

In this note we describe a family of arguments that link the homotopy-type of a) the diffeomorphism group of the disc $D^n$, b) the space of co-dimension one embedded spheres in a sphere and c) the homotopy-type of the space of co-dimension…

Geometric Topology · Mathematics 2024-07-12 Ryan Budney

We compute the homology of the multiple point spaces of stable perturbations of two germs $(\mathbb{C}^n,0)\to (\mathbb{C}^{n+1},0)$ of corank 2, one with $n=3$ and one with $n=5$. We use a variety of techniques based on the image computing…

Algebraic Geometry · Mathematics 2016-10-06 David Mond

In this paper, we study the topology of real analytic map-germs with isolated critical value $f: (\mathbb{R}^m,0) \to (\mathbb{R}^n,0)$, with $1 <n <m$. We compare the topology of $f$ with the topology of the compositions $\pi_i^* \circ f$,…

Differential Geometry · Mathematics 2016-04-29 Aurelio Menegon Neto , José Seade

Consider a singular holomorphic map-germ $f: (X,\underline{0}) \to (\mathbb C,0)$ where $X$ is a singular complex analytic variety in $\mathbb C^N$, and another holomorphic map-germ $g: (X,\underline{0}) \to (\mathbb C,0)$ which is…

Algebraic Geometry · Mathematics 2025-10-20 Lê Dũng Tráng , Juan J. Nuño-Ballesteros , José Seade

We prove under certain conditions that any stable unfolding of a quasi-homogeneous map-germ with finite singularity type is substantial. We then prove that if an equidimensional map-germ is finitely determined, of corank 1, and either it…

Algebraic Geometry · Mathematics 2025-04-09 Ignacio Breva Ribes , Raúl Oset Sinha

The paper is devoted to the study of homotopy properties of stabilizers of smooth functions on oriented surfaces, i.e., groups of diffeomorphisms of surfaces preserving a given function. For some class of smooth functions which is a…

Geometric Topology · Mathematics 2026-05-06 Bohdan Feshchenko

The number of Morse points in a Morsification determines the topology of the Milnor fibre of a holomorphic function germ $f$ with isolated singularity. If $f$ has an arbitrary singular locus, then this nice relation to the Milnor fibre…

Algebraic Geometry · Mathematics 2024-10-07 Mihai Tibăr

Let $M$ be a smooth compact connected surface, $P$ be either the real line $\mathbb{R}$ or the circle $S^1$ and $f:M\to P$ be a Morse map. Denote by $\mathcal{S}(f)$ and $\mathcal{O}(f)$ the corresponding stabilizer and orbit of $f$ with…

Geometric Topology · Mathematics 2014-08-21 Sergiy Maksymenko
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