Extension from lc centres and the extension theorem of Demailly but with estimates

Tsz On Mario Chan

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arXiv · 1811.02204

Extension from lc centres and the extension theorem of Demailly but with estimates

Tsz On Mario Chan

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Abstract

This paper generalises the result of Jean-Pierre Demailly on his Ohsawa--Takegoshi-type $L^2$ extension theorem, which guarantees holomorphic extensions for some sections $f$ on analytic subspaces $Y$ defined by multiplier ideal sheaves of plurisubharmonic functions. The result in this paper provides $L^2$ estimates for the extended sections even if those $f$ do not vanish on the singular sets of the reduced loci of the subspaces $Y$, at least for the case when the ambient manifold $X$ is compact and the relevant metrics have only neat analytic singularities. This is achieved by replacing the generalised Ohsawa measure by a measure supported on log-canonical centres.

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Tsz On Mario Chan. 2018-11-06. Extension from lc centres and the extension theorem of Demailly but with estimates. https://arxiv.org/abs/1811.02204

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