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Title of object: trivial valuation
Canonical Name: TrivialValuation
Type: Definition

Created on: 2004-04-29 03:00:33
Modified on: 2004-04-29 10:17:44

Creator: pahio
Modifier: pahio
Author: pahio

Classification: msc:11R99, msc:12J20

Preamble:

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Content:

The {\em trivial valuation} of a field $K$ is the mapping $|\cdot|$ from $K$ to $\mathbb{R}$ such that $|0| = 0$ and $|a| = 1$ for other elements $a$ of $K$.
\subsection*{Properties}
\begin{enumerate}
\item The trivial valuation is non-archimedean.
\item Every field has the trivial valuation. (If $a^m = 1$ in a finite field and $|\cdot|$ is its valuation, then $|a|^m = |a^m| = |1| = 1$ and thus $|a| = 1$.)
\item A finite field has only the trivial valuation.
\item Every infinite field has at least one non-trivial valuation.
\end{enumerate}