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Viewing Version 6 of 'orbit-stabilizer theorem'
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Title of object: orbit-stabilizer theorem
Canonical Name: OrbitStabilizerTheorem
Type: Theorem

Created on: 2002-02-19 06:41:46-05
Modified on: 2003-02-11 17:19:31.796183-05

Creator: vitriol
Modifier: vitriol
Author: vitriol

Preamble:

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Content:

Given a group action $G$ on a set $X$, define $Gx$ to be the orbit of $x$ and $G_x$ to be the set of stabilizers of $x$. For each $x \in X$ the correspondence $\operatorname{g}(x) \rightarrow gG_x$ is a bijection between $Gx$, and the set of left cosets of $G_x$
A famous corollary is that
$|\operatorname{G}(x)|.|G_x| = |G| \quad \forall x\in X$