An alternative to Witt vectors

Joachim Cuntz; Christopher Deninger

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arXiv · 1311.2774

An alternative to Witt vectors

Joachim Cuntz·Christopher Deninger

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Abstract

The ring of Witt vectors associated to a ring R is a classical tool in algebra. We introduce a ring C(R) which is more easily constructed and which is isomorphic to the ring of Witt vectors W(R) for a perfect F_p-algebra R. It is obtained as the completion of the monoid ring ZR, for the multiplicative monoid R, with respect to the powers of the kernel of the natural map from ZR to R.

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Joachim Cuntz, Christopher Deninger. 2013-12-18. An alternative to Witt vectors. https://arxiv.org/abs/1311.2774

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