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Related papers: Milnor numbers and Euler obstruction

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Let $f: M \to N$ be a holomorphic map between two complex manifolds. Assume $f$ is flat and sans \'{e}clatement en codimension 0 (no blowup in codimension 0). We study the theory of Lagrangian specialisation for such $f$, and prove a…

Algebraic Geometry · Mathematics 2018-08-30 Xia Liao

We compare the Euler-Poincar\'e characteristic to the global Euler obstruction, in case of singular affine varieties, and point out a certain duality among their expressions in terms of strata of a Whitney stratification.

Complex Variables · Mathematics 2007-08-21 Mihai Tibăr

This is the beginning of an obstruction theory for deciding whether a map f:S^2 --> X^4 is homotopic to a topologically flat embedding, in the presence of fundamental group and in the absence of dual spheres. The first obstruction is Wall's…

Geometric Topology · Mathematics 2014-10-01 Rob Schneiderman , Peter Teichner

We show a lower estimate of the Milnor number of an isolated hypersurface singularity, via its Newton number. We also obtain analogous estimate of the Milnor number of an isolated singularity of a similar complete intersection variety.

Algebraic Geometry · Mathematics 2007-05-23 Masako Furuya

We give a necessary condition for a meromorphic function in several variables to give rise to a Milnor fibration of the local link (respectively of the link at infinity). In the case of two variables we give some necessary and sufficient…

Algebraic Geometry · Mathematics 2007-05-23 Arnaud Bodin , Anne Pichon

Let $X \subset \Bbb{C}^n$ be an equidimensional complex algebraic set and let $f: X \to \mathbb{C}$ be a polynomial function. For each $c \in \Bbb{C}$, we define the global Brasselet number of $f$ at $c$, a global counterpart of the…

Algebraic Geometry · Mathematics 2019-05-15 Nicolas Dutertre , Nivaldo G. Grulha

The Milnor number of an isolated hypersurface singularity, defined as the codimension $\mu(f)$ of the ideal generated by the partial derivatives of a power series $f$ whose zeros represent locally the hypersurface, is an important…

Algebraic Geometry · Mathematics 2023-08-15 Abramo Hefez , João Helder Olmedo Rodrigues , Rodrigo Salomão

We show that there are obstructions to the existence of certain types of invariant subspaces of the Milnor monodromy; this places restrictions on the cohomology of Milnor fibres of non-isolated hypersurface singularities.

Algebraic Geometry · Mathematics 2007-05-23 David B. Massey

We study holomorphic vector fields whose singular locus contains a local complete intersection smooth positive-dimensional component. We prove global and local formulas expressing the limiting Milnor/Poincare-Hopf contribution along such a…

Algebraic Geometry · Mathematics 2026-02-11 Maurício Corrêa , Gilcione Nonato Costa , Alejandra Salamanca Russi

We consider partial liftings of maps at fibrations and compare the primary obstruction to extend the lifting with the obstruction to extend the lifting as a simple map into the total space. A relation between these two obstructions is…

Algebraic Topology · Mathematics 2007-05-23 Christian Bohr

In this work we investigate the topological information captured by the Euler obstruction of a map, $f:(X,0)\to (\mathbb{C}^{2},0)$, with $(X,0)$ a germ of a complex $d$-equidimensional singular space, with $d > 2$, and its relation with…

Geometric Topology · Mathematics 2020-09-18 Nivaldo G. Grulha , Camila Ruiz , Hellen Santana

We study the vanishing neighbourhood of non-isolated singularities of functions on singular spaces by associating a general linear function. We use the carrousel monodromy in order to show how to get a better control over the attaching of…

Complex Variables · Mathematics 2016-09-07 Mihai Tibar

We give conditions for when two Euler products are the same given that they satisfy a functional equation and their coefficients are not too large and do not differ from each other by too much. Additionally, we prove a number of…

Number Theory · Mathematics 2025-05-13 David W. Farmer , Ameya Pitale , Nathan C. Ryan , Ralf Schmidt

We discuss and prove a number of cohomological results for Milnor fibers, real links, and complex links of local complete intersections with singularities of arbitrary dimension.

Algebraic Geometry · Mathematics 2014-02-24 David B. Massey

We determine the topological Euler number of certain moduli space of 1-dimensional closed subschemes in a smooth projective variety which admits a Zariski-locally trivial fibration with 1-dimensional fibers. The main approach is to use…

Algebraic Geometry · Mathematics 2007-05-23 Wei-Ping Li , Zhenbo Qin

Convenient mixed functions with strongly non-degenerate Newton boundaries have Milnor fibrations, as the isolatedness of the singularity follows from the convenience. In this paper, we consider the Milnor fibration for non-convenient mixed…

Algebraic Geometry · Mathematics 2014-09-24 Mutsuo Oka

In this paper, we investigate the local Euler obstruction and the relative local Euler obstruction in terms of constructible complexes of sheaves, characteristic cycles, and vanishing cycles. The fundamental tool that we use is the notion…

Algebraic Geometry · Mathematics 2017-05-03 David B. Massey

We define motivic Milnor fiber of cyclic $L_\infty$-algebras of dimension three using the method of Denef and Loeser of motivic integration. It is proved by Nicaise and Sebag that the topological Euler characteristic of the motivic Milnor…

Algebraic Geometry · Mathematics 2010-02-19 Yunfeng Jiang

On a M\"obius surface, as defined by D. Calderbank, we study a variant of the Einstein-Weyl (EW) equation which we call scalar-flat M\"obius EW (sf-MEW). This is a conformally invariant, finite type, overdetermined system of semi-linear…

Differential Geometry · Mathematics 2013-10-09 Matthew Randall

It is well known that the diffeomorphism-type of the Milnor fibration of a (Newton) non-degenerate polynomial function $f$ is uniquely determined by the Newton boundary of $f$. In the present paper, we generalize this result to certain…

Algebraic Geometry · Mathematics 2021-08-19 Christophe Eyral , Mutsuo Oka