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arXiv · 2006.10878

$K$-theory of locally compact modules over orders

Oliver Braunling·Ruben Henrard·Adam-Christiaan van Roosmalen
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Abstract

We present a quick approach to computing the $K$-theory of the category of locally compact modules over any order in a semisimple $\mathbb{Q}$-algebra. We obtain the $K$-theory by first quotienting out the compact modules and subsequently the vector modules. Our proof exploits the fact that the pair (vector modules plus compact modules, discrete modules) becomes a torsion theory after we quotient out the finite modules. Treating these quotients as exact categories is possible due to a recent localization formalism.

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Oliver Braunling, Ruben Henrard, Adam-Christiaan van Roosmalen. 2020-06-18. $K$-theory of locally compact modules over orders. https://arxiv.org/abs/2006.10878

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