Kodai Mathematical Journal

Topological triviality of linear deformations with constant Lê numbers

Christophe Eyral and Maria Aparecida Soares Ruas

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Let f(t,z) = f0(z) + tg(z) be a holomorphic function defined in a neighbourhood of the origin in C × Cn. It is well known that if the one-parameter deformation family {ft} defined by the function f is a μ-constant family of isolated singularities, then {ft} is topologically trivial—a result of A. Parusiński. It is also known that Parusiński's result does not extend to families of non-isolated singularities in the sense that the constancy of the Lê numbers of ft at 0, as t varies, does not imply the topological triviality of the family ft in general—a result of J. Fernández de Bobadilla. In this paper, we show that Parusiński's result generalizes all the same to families of non-isolated singularities if the Lê numbers of the function f itself are defined and constant along the strata of an analytic stratification of C × (f0−1(0) $\cap$ g−1(0)). Actually, it suffices to consider the strata that contain a critical point of f.

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Kodai Math. J., Volume 39, Number 1 (2016), 189-201.

First available in Project Euclid: 22 March 2016

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Eyral, Christophe; Ruas, Maria Aparecida Soares. Topological triviality of linear deformations with constant Lê numbers. Kodai Math. J. 39 (2016), no. 1, 189--201. doi:10.2996/kmj/1458651699. https://projecteuclid.org/euclid.kmj/1458651699

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