$\mathbb{Z} R$ and rings of Witt vectors $W_S (R)$

Christopher Deninger; Anton Mellit

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arXiv · 1803.00812

$\mathbb{Z} R$ and rings of Witt vectors $W_S (R)$

Christopher Deninger·Anton Mellit

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Abstract

Using $\lambda$ operations, we give some results on the kernel of the natural map from the monoid algebra $\mathbb{Z} R$ of a commutative ring $R$ to the ring of $S$-Witt vectors of $R$. As a byproduct we obtain a very natural interpretation of a power series used by Dwork in his proof of the rationality of zeta functions for varieties over finite fields.

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BibTeX RIS

Christopher Deninger, Anton Mellit. 2018-03-02. $\mathbb{Z} R$ and rings of Witt vectors $W_S (R)$. https://arxiv.org/abs/1803.00812

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