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Tangencial base points on algebraic stacks

V. Zoonekynd
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Abstract

The notion of tangencial base point is well-known for schemes in characteristic zero. We show that the definition in terms of Puiseux series generalizes to the case of Deligne--Mumford stacks, over a field of arbitrary characteristic. We then apply this construction to moduli spaces of smooth curves, generalizing a result of Ihara-Nakamura.

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V. Zoonekynd. 2001-11-07. Tangencial base points on algebraic stacks. https://arxiv.org/abs/math/0111072

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