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Is there a classification of the finite subgroups of $PGSp_4(\mathbb{C})$?

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    $\begingroup$ These are the same as those in the maximal compact subgroup, $\mathrm{PSp}(4)$, which in turn is (by an exceptional isomorphism) is isomorphic to $\mathrm{SO}(5)$. (So the isomorphism classification is the same, although I'm not completely sure that for a complex semisimple group $G$ with compact maximal subgroup $K$, whether two finite subgroups of $K$ that are conjugate in $G$ are always conjugate in $G$, so I'm not firm about claiming that the classification up to conjugation is the same) $\endgroup$
    – YCor
    Commented Jun 3, 2016 at 11:03
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    $\begingroup$ I search a classification. Example : the finite subgroups of $PGL_2(\mathbb{C})$ are the dihedral groups D_2n and A_5 S_4 and S_5 ..... And I want an answer like this or a reference. I didn't speak about compact but finite groups. $\endgroup$ Commented Jun 3, 2016 at 11:59
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    $\begingroup$ I understand that you asked about finite subgroups. Anyway my comment was about maximal compact subgroups which is the first step towards understanding finite subgroups. $\endgroup$
    – YCor
    Commented Jun 3, 2016 at 12:18
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    $\begingroup$ As someone who isn't a group theorist, I am a bit puzzled by the downvote and the votes to close... $\endgroup$
    – Yemon Choi
    Commented Jun 3, 2016 at 13:01
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    $\begingroup$ @YemonChoi The question itself is reasonable. But a little more context would have been good! For example the poster could have included their comment above in the original question. $\endgroup$
    – Derek Holt
    Commented Jun 3, 2016 at 14:18

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