On the arithmetic fundamental groups

Feng-Wen An

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arXiv · 0910.0605

On the arithmetic fundamental groups

Feng-Wen An

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Abstract

In this paper we will define a qc fundamental group for an arithmetic scheme by quasi-galois closed covers. Then we will give a computation for such a group and will prove that the etale fundamental group of an arithmetic scheme is a normal subgroup in our qc fundamental group, which make up the main theorem of the paper. Hence, our group gives us a prior estimate of the etale fundamental group. The quotient group reflects the topological properties of the scheme.

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Feng-Wen An. 2009-12-20. On the arithmetic fundamental groups. https://arxiv.org/abs/0910.0605

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