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Viewing Version 6 of 'Reflexive non-degenerate sesquilinear'
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Title of object: Reflexive non-degenerate sesquilinear
Canonical Name: ReflexiveNonDegenerateSesquilinear
Type: Definition

Created on: 2006-04-14 19:28:37
Modified on: 2006-06-19 13:05:13

Creator: Algeboy
Modifier: Algeboy
Author: Algeboy

Classification: msc:15A63
Keywords: Reflexive
Defines: Reflexive non-degenerate sesquilinear, Reflexive non-degenerate bilinear, Reflexive
Synonyms: Reflexive non-degenerate sesquilinear=reflexive non-degenerate bilinear
Reflexive non-degenerate sesquilinear=reflexive sesquilinear
Reflexive non-degenerate sesquilinear=reflexive bilinear

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

Changes for correction #9531 ('capitalization').

Preamble:

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\usepackage{amsfonts}
\usepackage{amsthm}

\usepackage{xypic}

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Content:

A non-degenerate sesquilinear form $b:V\times V\rightarrow k$ is \emph{reflexive} if for all $v,w\in V$, if $b(v,w)=0$ then $b(w,v)=0$. This means
\[v\perp w\textnormal{ if and only if } w\perp v.\]
It is rare to define perpendicularity for sesquilinear/bilinear maps which are not reflexive because it would require a version of left and right perpendicular. Thus a reflexive sesquilinear/bilinear map is usually synonymous with the existence of perpendicularity.