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arXiv · 1908.03941

Galois Cohomology for Lubin-Tate $(\varphi_q,\Gamma_{LT})$-modules over Coefficient rings

Chandrakant Aribam·Neha Kwatra
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Abstract

The classification of the local Galois representations using $(\varphi,\Gamma)$-modules by Fontaine has been generalized by Kisin and Ren over the Lubin-Tate extensions of local fields using the theory of $(\varphi_q,\Gamma_{LT})$-modules. In this paper, we extend the work of (Fontaine) Herr by introducing a complex which allows us to compute cohomology over the Lubin-Tate extensions and compare it with the Galois cohomology groups. We further extend that complex to include certain non-abelian extensions. We then deduce some relations of this cohomology with those arising from $(\psi_q,\Gamma_{LT})$-modules. We also compute the Iwasawa cohomology over the Lubin-Tate extensions in terms of $\psi_q$-operator acting on the \'{e}tale $(\varphi_q,\Gamma_{LT})$-module attached to the local Galois representation. Moreover, we generalize the notion of $(\varphi_q,\Gamma_{LT})$-modules over the coefficient ring $R$ and show that the equivalence given by Kisin and Ren extends to the Galois representations over $R$. This equivalence allows us to generalize our results to the case of coefficient rings.

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Chandrakant Aribam, Neha Kwatra. 2019-08-11. Galois Cohomology for Lubin-Tate $(\varphi_q,\Gamma_{LT})$-modules over Coefficient rings. https://arxiv.org/abs/1908.03941

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