Breuil-Kisin Modules via crystalline cohomology

Bryden Cais; Tong Liu

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arXiv · 1610.09706

Breuil-Kisin Modules via crystalline cohomology

Bryden Cais·Tong Liu

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Abstract

For a perfect field $k$ of characteristic $p>0$ and a smooth and proper formal scheme $\mathscr{X}$ over the ring of integers of a finite and totally ramified extension $K$ of $W(k)[1/p]$, we propose a cohomological construction of the Breuil-Kisin modules attached to the $p$-adic \'etale cohomology $H^i_{\mathrm{\'et}}(\mathscr{X}_{\overline{K}},\mathbf{Z}_p)$. We then prove that our proposal works when $p>2$, $i < p-1$, and the crystalline cohomology of the special fiber of $\mathscr{X}$ is torsion-free in degrees $i$ and $i+1$.

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Bryden Cais, Tong Liu. 2016-10-30. Breuil-Kisin Modules via crystalline cohomology. https://arxiv.org/abs/1610.09706

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