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arXiv · 0908.1503

1-t-motifs

Lenny Taelman
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Abstract

We show that the module of rational points on an abelian t-module E is canonically isomorphic with the module Ext^1(M_E, K[t]) of extensions of the trivial t-motif K[t] by the t-motif M_E associated with E. This generalizes prior results of Anderson and Thakur, Papanikolas and Ramachandran, and Woo. In case E is uniformizable then we show that this extension module is canonically isomorphic with the corresponding extension module of Pink-Hodge structures. This situation is formally very similar to Deligne's theory of 1-motifs and we have tried to build up the theory in a way that makes this analogy as clear as possible.

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Lenny Taelman. 2009-08-11. 1-t-motifs. https://arxiv.org/abs/0908.1503

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