2026/03/31 by Filippo Valnegri
Mathematics · #math.CV #msc:32F10 #msc:32U05 #msc:32V40
arxiv created 2026/08/03 · arxiv updated 2026/08/04
The aim of this article is to find under which conditions there exists a foliation by n-dimensional complex manifolds on a closed subset Z⊂ℂN, which is locally a continuous graph over a closed subset of ℂn×ℝ. We prove that such foliation does exist if Z is q-pseudoconcave, for any q≥ n. We also prove that this bound on the index of pseudoconcavity is sharp. Namely, we construct many q-pseudoconcave subsets of ℂN, for q<n, which are smooth graphs over closed subsets of ℂn×ℝ but with no analytic structure. As an application, we show that an n-pseudoconcave set sitting in a subset of ℂN, which is locally a differentiable graph over a domain of ℝ2n+1, is foliated by n-dimensional complex manifolds.