On natural homomorphisms of Witt rings

Ciemała, Marzena; Szymiczek, Kazimierz

doi:10.1090/S0002-9939-05-07896-2

On natural homomorphisms of Witt rings
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by Marzena Ciemała and Kazimierz Szymiczek PDF

Proc. Amer. Math. Soc. 133 (2005), 2519-2523 Request permission

Abstract:

We prove that the kernel of the ring homomorphism between the Witt ring of any order of a global field and the Witt ring of the field is a nilideal.

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