arXiv subjects

Nobuhiro Higuchi

Publications and source records attributed to Nobuhiro Higuchi.

3 recordsLinked to original sources

arXiv2019

On the boundary components of central streams

Foliations on the space of $p$-divisible groups were studied by Oort in 2004. In his theory, special leaves called central stream play an important role. In this paper, we give a complete classification of the boundary components of the central streams for an arbitrary Newton polygon in the unpolarized case. Hopefully this classification would help us to know the boundaries of other leaves and more detailed structure of the boundaries of central streams.

math.AG↗

arXiv2018

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

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.

math.AG↗

arXiv2017

On specializations of minimal $p$-divisible groups

In this paper, for any pair $(\zeta, \xi)$ of Newton polygons with $\zeta \prec \xi$, we construct a concrete specialization from the minimal $p$-divisible group of $\xi$ to the minimal $p$-divisible group of $\zeta$ by a beautiful induction. This in particular gives the affirmative answer to the unpolarized analogue of a question by Oort on the boundaries of central streams, and gives another proof of the dimension formula of the central leaves in the unpolarized case.

math.AG↗