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Viewing Version 1 of 'complete ultrametric field'
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Title of object: complete ultrametric field
Canonical Name: CompleteUltrametricField
Type: Theorem

Created on: 2005-01-03 14:29:00
Modified on: 2005-01-03 14:29:00

Creator: pahio
Modifier: pahio
Author: pahio

Classification: msc:54E35, msc:12J10
Keywords: convergence
Defines: ultrametric field, non-archimedean field

Preamble:

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Content:

A field $K$ together with its ultrametric $d$ is an {\em ultrametric field}; we can also speak of a {\em non-archimedean field} if the ultrametric is induced by a \PMlinkname{non-archimedean}{KrullValuation} valuation of $K$.



\textbf{Theorem.} \,Let $(K,\,d)$ be an ultrametric field. \,A necessary and sufficient condition for the convergence of the series \,$a_1+a_2+...$\, in $K$ is that
$$\lim_{n\to\infty}a_n = 0.$$