MHB Can a Finite Group Acting on a Set Have No Fixed Points?

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A finite group acting transitively on a finite set with more than one element must have at least one element that acts without fixed points. The problem presented emphasizes the existence of such an element in the context of group actions. Solutions were provided by users castor28 and Olinguito, highlighting the mathematical reasoning behind the conclusion. The discussion encourages engagement with the Problem of the Week format. The topic underscores fundamental concepts in group theory and set actions.
Euge
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Here is this week's POTW:

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Let $X$ be a finite set with more than one element, and $G$ be a finite group acting transitively on $X$. Show that some element of $G$ is free of fixed points.

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Remember to read the https://mathhelpboards.com/showthread.php?772-Problem-of-the-Week-%28POTW%29-Procedure-and-Guidelines to find out how to https://mathhelpboards.com/forms.php?do=form&fid=2!
 
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This week's problem was solved correctly by castor28 and Olinguito. You can read castor28's solution below.
Let $|X|=n>1$. As the action is transitive, there is only one orbit. By Burnside's lemma, this is equal to the average number of points fixed by an element of $G$.
The identity of $G$ fixes all the $n$ points. If every element of $G$ fixed at least one point, the average would be grater than $1$.
 

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