Abstract
We introduce the abelian class group C ab (G) of a reductive group scheme G over a ring A of arithmetical interest and study some of its basic properties. For example, we show that if the fraction field of A is a global field without real primes, then there exists a surjection C(G) ↠ C ab (G), where C(G) is the class set of G.
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The author is partially supported by Fondecyt grant 1080025.
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González-Avilés, C.D. Abelian class groups of reductive group schemes. Isr. J. Math. 196, 175–214 (2013). https://doi.org/10.1007/s11856-012-0147-4
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DOI: https://doi.org/10.1007/s11856-012-0147-4