Singular holomorphic functions for which all fibre-integrals are smooth
Volume 74 / 2000
Annales Polonici Mathematici 74 (2000), 65-77
DOI: 10.4064/ap-74-1-65-77
Abstract
For a germ (X,0) of normal complex space of dimension n + 1 with an isolated singularity at 0 and a germ f: (X,0) → (ℂ,0) of holomorphic function with df(x) ≤ 0 for x ≤ 0, the fibre-integrals $s ↦ ∫_{f=s} ϱ ω' ⋀ \bar{ω''}, ϱ ∈ C^{∞}_{c}(X), ω', ω'' ∈ Ω_{X}^{n}$, are $C^{∞}$ on ℂ* and have an asymptotic expansion at 0. Even when f is singular, it may happen that all these fibre-integrals are $C^{∞}$. We study such maps and build a family of examples where also fibre-integrals for $ω',ω'' ∈ ⍹_{X}$, the Grothendieck sheaf, are $C^{∞}$.