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Viewing Version 4 of 'anti-isomorphism'
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Title of object: anti-isomorphism
Canonical Name: AntiIsomorphism
Type: Definition

Created on: 2006-06-17 23:09:39
Modified on: 2006-06-18 09:23:57

Creator: Mathprof
Modifier: Mathprof
Author: Mathprof

Classification: msc:16B99, msc:13B10
Defines: anti-endomorphism

Preamble:

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Content:

Let $R$ and $S$ be rings. A function $f: R \longrightarrow S$ is said to be an {\it anti-isomorphism} if it is an
isomorphism of the additive groups of $R$ and $S$ and
$f(r_{1}r_{2}) = f(r_{2})f(r_{1})$ for all $r_{1}, r_{2} \in R$.

If $R=S$, then $f$ is called an {\it anti-endomorphism}.