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Viewing Version 3 of 'analytic algebraic function'
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Title of object: analytic algebraic function
Canonical Name: AnalyticAlgebraicFunction
Type: Definition

Created on: 2005-12-05 20:51:43
Modified on: 2005-12-07 10:39:14

Creator: jirka
Modifier: jirka
Author: jirka

Classification: msc:14-00, msc:14P20
Defines: holomorphic algebraic function, real-analytic algebraic function, Nash function, analytic algebraic mapping
Synonyms: analytic algebraic function=$k$-analytic algebraic function
analytic algebraic function=analytic algebraic

Revision comment (for changes between this and next version):

Changes for correction #7308 ('Metric on k?').

Preamble:

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Content:

Let $k$ be a field, and let $k\{x_1,\ldots,x_n\}$ be the ring of convergent
power series in $n$ variables. An element in this ring can be thought of as
a function defined in a neighbourhood of the origin in $k^n$ to $k$.

\begin{defn}
A function $f \in k\{x_1,\ldots,x_n\}$ is said to be \emph{$k$-analytic
algebraic} if there exists a nontrivial polynomial $p \in
k[x_1,\ldots,x_n,y]$ such that $p(x,f(x)) \equiv 0$ for all $x$ in a
neighbourhood of the origin in $k^n$.
If $k=\mathbb{C}$ then $f$ is said to be \emph{holomorphic algebraic} and if
$k=\mathbb{R}$ then $f$ is said to be \emph{real-analytic algebraic} or a
\emph{Nash function}.
\end{defn}

The same definition applies near any other point other then the origin by just translation. The field need not be $\mathbb{C}$ or $\mathbb{R}$ but those are the most common cases.

\begin{defn}
A mapping $f \colon U \subset k^n \to k^m$ where $U$ is a neighbourhood of the origin is said to be $k$-analytic algebraic if each component function is analytic algebraic.
\end{defn}

\begin{thebibliography}{9}
\bibitem{ber:submanifold}
M.\@ Salah Baouendi,
Peter Ebenfelt,
Linda Preiss Rothschild.
{\em \PMlinkescapetext{Real Submanifolds in Complex Space and Their Mappings}},
Princeton University Press,
Princeton, New Jersey, 1999.
\end{thebibliography}