English
Related papers

Related papers: Milnor and Tjurina numbers for a hypersurface germ…

200 papers

In this paper, we use Hilbert-Samuel multiplicity, Hilbert-Kunz multiplicity, and s-multiplicity to establish a sharp upper bound for the quotient of the generalized Milnor numbers and the Tjurina numbers for isolated hypersurface…

Algebraic Geometry · Mathematics 2026-04-21 Hongrui Ma , Huaiqing Zuo

Let $(\bf {V,0})\subset (\mathbb{C}^n,0)$ be a germ of a complex hypersurface and let $f: (\mathbb{C}^n,0)\to(\mathbb{C}^n,0)$ be a germ of a finite holomorphic mapping. If germs $(\bf {V,0})$ and ${\bf W}:=(F^{-1}(\bf{ V})),0)$ are…

Complex Variables · Mathematics 2023-01-24 Zbigniew Jelonek

For an isolated hypersurface singularity $f=0$, the Milnor number $\mu$ is greater than or equal to the Tjurina number $\tau$ (the dimension of the base of the semi-universal deformation), with equality if $f$ is quasi-homogeneous. K. Saito…

Algebraic Geometry · Mathematics 2016-03-28 Jonathan Wahl

The Tjurina ideal of a germ of an holomorphic function $f$ is the ideal of $\mathscr{O}_{\mathbbm{C}^n,0}$ - the ring of those germs at $0\in\mathbbm{C}^n$ - generated by $f$ itself and by its partial derivatives. Here it is denoted by…

Algebraic Geometry · Mathematics 2023-07-11 João Helder Olmedo Rodrigues

In this paper, we introduce the notions of the $k$-th Milnor number and the $k$-th Tjurina number for a germ of holomorphic foliation on the complex plane with an isolated singularity at the origin. We develop a detailed study of these…

Complex Variables · Mathematics 2025-11-11 Marcela Ribeiro , Arturo Fernández-Pérez

In this note we provide a formula for the Tjurina number of a join of isolated hypersurface singularities in separated variables. From this we are able to provide a characterization of isolated hypersurface singularities whose difference…

Algebraic Geometry · Mathematics 2022-05-26 Patricio Almirón

This paper aims to prove that given a isolated complete intersection singularity, the Milnor number will be bounded by a bound depending only on Tjurina number and dimension of the singularity. The proof uses A$\mathfrak{m}$AC (introduced…

Algebraic Geometry · Mathematics 2023-05-31 A. J. Parameswaran , Mohit Upmanyu

We describe a generalization of Milnor's formula for the Milnor number of an isolated hypersurface singularity to the case of a function $f$ whose restriction $f|(X,0)$ to an arbitrarily singular reduced complex analytic space $(X,0)…

Algebraic Geometry · Mathematics 2020-02-11 Matthias Zach

For function germs $g:(\mathbb C^n,0)\to (\mathbb C,0)$ it is well known that $1\leq\frac{\mu(g)}{\tau(g)}$ and it has recently been proved by Liu that $\frac{\mu(g)}{\tau(g)}\leq n$. We give an upper bound for the codimension of map-germs…

Algebraic Geometry · Mathematics 2023-05-24 Ignacio Breva Ribes , Raúl Oset Sinha

Let $ \Phi: ({\mathbb C}^2, 0) \to ( {\mathbb C}^3, 0) $ be a finitely determined complex analytic germ and let $(\{f=0\},0)$ be the reduced equation of its image, a non-isolated hypersurface singularity. We provide the plumbing graph of…

Algebraic Geometry · Mathematics 2019-02-05 András Némethi , Gergő Pintér

We show three basic properties on the image Milnor number $\mu_I(f)$ of a germ $f\colon(\mathbb{C}^{n},S)\rightarrow(\mathbb{C}^{n+1},0)$ with isolated instability. First, we show the conservation of the image Milnor number, from which one…

Algebraic Geometry · Mathematics 2021-07-05 R. Giménez Conejero , J. J. Nuño-Ballesteros

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 $f$ that represents locally the hypersurface, is an important topological…

Algebraic Geometry · Mathematics 2023-07-25 Abramo Hefez , João Helder Olmedo Rodrigues , Rodrigo Salomão

We study functions on isolated singularities and prove some results of type Milnor number = Tjurina number. We use them to endow the base space of their miniversal deformation with the structure of F-manifold.

Algebraic Geometry · Mathematics 2007-05-23 Ignacio de Gregorio

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

We extend the notion of $\mu^*$-sequence and Tjurina number of functions to the framework of Bruce-Roberts numbers, that is, to pairs formed by the germ at $0$ of a complex analytic variety $X\subseteq \mathbb C^n$ and a finitely $\mathcal…

Algebraic Geometry · Mathematics 2018-10-26 Carles Bivià-Ausina , María Aparecida Soares Ruas

We prove a lower bound for the Milnor number of function germ invariant with respect to a finite abelian group action. It is shown that this bound is tight for functions of arbitrarily many variables. We also prove the function germs that…

Algebraic Geometry · Mathematics 2026-01-14 Ivan Proskurnin

We show that the possible drop in multiplicity in an analytic family $F(z,t)$ of complex analytic hypersurface singularities with constant Milnor number is controlled by the powers of $t$. We prove equimultiplicity of $\mu$-constant…

Algebraic Geometry · Mathematics 2012-06-11 Camille Plenat , David Trotman

A set of Morse numbers is associated to a holomorphic function germ with stratified isolated singularity, extending the classical Milnor number to the setting of a singular base space.

Complex Variables · Mathematics 2024-03-04 Laurentiu Maxim , Mihai Tibăr

In this paper we give a positive answer to a question of Dimca and Greuel about the quotient between the Milnor and the Tjurina numbers for any irreducible germ of plane curve singularity. This result is based on a closed formula for the…

Algebraic Geometry · Mathematics 2020-01-08 Maria Alberich-Carramiñana , Patricio Almirón , Guillem Blanco , Alejandro Melle-Hernández

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
‹ Prev 1 2 3 10 Next ›