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arXiv · 1108.3945

A remark on vanishing cycles with two strata

Lê Dũng Tráng·David B. Massey
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Abstract

Suppose that the critical locus $Σ$ of a complex analytic function $f$ on affine space is, itself, a space with an isolated singular point at the origin $\0$, and that the Milnor number of $f$ restricted to normal slices of $Σ-\{\0\}$ is constant. Then, the general theory of perverse sheaves puts severe restrictions on the cohomology of the Milnor fiber of $f$ at $\0$, and even more surprising restrictions on the cohomology of the Milnor fiber of generic hyperplane slices.

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Lê Dũng Tráng, David B. Massey. 2011-08-19. A remark on vanishing cycles with two strata. https://arxiv.org/abs/1108.3945

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