Find All Transitive G-Sets Up to Isomorphism w/ Subgroups of G

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daveyinaz
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I read in a book on groups and representations that any transitive [tex]G[/tex]-set is isomorphic to the coset space of some subgroup of [tex]G[/tex].
Does this mean we can determine all transitive [tex]G[/tex]-sets up to isomorphism simply by finding all subgroups of [tex]G[/tex]?

Just want to make sure that if this is the case that I have in my mind the right idea, so we take [tex]G = S_3[/tex], then all transitive [tex]G[/tex]-sets are up to isomorphism...
[tex]G / \{e\}, G / \langle (12) \rangle , G / \langle (132) \rangle , G / G[/tex]?

Note I do realize that [tex]\langle (13) \rangle[/tex] is also a subgroup of [tex]S_3[/tex] but the way I see it the coset space would be the same as [tex]G / \langle (12) \rangle[/tex]
 
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That's correct, except that the coset space of a subgroup of G is not in general a quotient group (since the subgroup may not be normal)
 
Well that would make sense right? Since a G-set isn't necessarily a group...and if it's isomorphic to some coset space, then that coset space isn't a group either.
 
Yup, but writing

[tex] G / \{e\}, G / \langle (12) \rangle , G / \langle (132) \rangle , G / G[/tex]

This is notation for quotient groups. If H is a subgroup of G, the set of cosets is often denoted cos(G:H)