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arXiv · 2204.07007

Symplectic monodromy at radius zero and equimultiplicity of $\mu$-constant families

Javier Fernández de Bobadilla·Tomasz Pełka
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Abstract

We show that every family of isolated hypersurface singularity with constant Milnor number has constant multiplicity. To achieve this, we endow the A'Campo model of "radius zero" monodromy with a symplectic structure. This new approach allows to generalize a spectral sequence of McLean converging to fixed point Floer homology of iterates of the monodromy to a more general setting which is well suited to study $\mu$-constant families.

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Javier Fernández de Bobadilla, Tomasz Pełka. 2022-04-14. Symplectic monodromy at radius zero and equimultiplicity of $\mu$-constant families. https://doi.org/10.4007/annals.2024.200.1.4

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