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arXiv · 1008.4234

The Carlitz shtuka

Lenny Taelman
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Abstract

Recently we have used the Carlitz exponential map to define a finitely generated submodule of the Carlitz module having the right properties to be a function field analogue of the group of units in a number field. Similarly, we constructed a finite module analogous to the class group of a number field. In this short note more algebraic constructions of these "unit" and "class" modules are given and they are related to Ext modules in the category of shtukas.

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Lenny Taelman. 2010-09-29. The Carlitz shtuka. https://doi.org/10.1016/j.jnt.2010.09.004

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