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arXiv · 2009.10512

On Vlasenko's formal group laws

Dingxin Zhang
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Abstract

Given a Laurent polynomial over a ring flat over \(\mathbb{Z}\), Vlasenko defines a formal group law. We identify this formal group law with a coordinate system of a formal group functor, prove its integrality. When the Hasse--Witt matrix of the Laurent polynomial is invertible, Vlasenko defines a matrix by taking a certain \(p\)-adic limit. We show that this matrix is the Frobenius of the Dieudonn\'e module of this formal group modulo \(p\).

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Dingxin Zhang. 2020-09-22. On Vlasenko's formal group laws. https://doi.org/10.1007/s00229-021-01353-z

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