$D$-local algebraic fundamental groups of germs of normal complex analytic singularities

Koji Ohno

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arXiv · 1502.05766

$D$-local algebraic fundamental groups of germs of normal complex analytic singularities

Koji Ohno

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Abstract

In this paper, the notion of local algebraic fundamental groups of normal complex analytic singularities are generalized to certain profinite groups called $D$-local algebraic fundamental groups which turns out to be useful even for the study of usual local algebraic fundamental groups and the Lefshetz type theorem for $D$-local algebraic fundamental groups is proved under certain conditions. The theorem yields, for example, the finiteness of the local algebraic fundamental groups of a certain class of four dimensional singularities and will be useful for the classification of three dimensional purely log terminal singularities.

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BibTeX RIS

Koji Ohno. 2015-02-20. $D$-local algebraic fundamental groups of germs of normal complex analytic singularities. https://arxiv.org/abs/1502.05766

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