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arXiv · 2311.07799

Comparisons of Lie algebra cohomologies of $(\varphi,\Gamma)$-modules

Rustam Steingart
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Abstract

We generalise a result of Fourquaux and Xie thereby completely determining the relationship between $\mathbb{Q}_p$ and $L$-analytic Lie algebra cohomology of analytic $(\varphi_L,\Gamma_L)$-modules. We use the results to conclude that for $L\neq \mathbb{Q}_p,$ there exist examples of \'etale $(\varphi_L,\Gamma_L)$-modules over Robba rings whose $\mathbb{Q}_p$-analytic cohomology does not arise as a base change of Galois cohomology.

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Rustam Steingart. 2023-11-13. Comparisons of Lie algebra cohomologies of $(\varphi,\Gamma)$-modules. https://arxiv.org/abs/2311.07799

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