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arXiv · 1805.07285

On the boundary components of central streams in the two slopes case

Nobuhiro Higuchi
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Abstract

In 2004 Oort studied the foliation on the space of $p$-divisible groups. In his theory, special leaves called central streams play an important role. It is still meaningful to investigate central streams, for example, there remain a lot of unknown things on the boundaries of central streams. In this paper, we classify the boundary components of the central stream for a Newton polygon consisting of two segments, where one slope is less than $1/2$ and the other slope is greater than $1/2$. Moreover we determine the generic Newton polygon of each boundary component using this classification.

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Nobuhiro Higuchi. 2018-05-18. On the boundary components of central streams in the two slopes case. https://arxiv.org/abs/1805.07285

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