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Timeline for Extending an infinite simple group

Current License: CC BY-SA 3.0

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Oct 30, 2015 at 11:37 history edited 喻 良 CC BY-SA 3.0
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Oct 30, 2015 at 11:17 vote accept 喻 良
Oct 30, 2015 at 10:59 answer added Derek Holt timeline score: 11
Oct 30, 2015 at 10:44 comment added 喻 良 If this argument works, then by a Skolemization including $H$, it holds for any cardinal $\kappa\geq|H|$.
Oct 30, 2015 at 10:33 comment added Derek Holt In general, if $|H| = \kappa$ with $\kappa$ infinite, then you can embed $H$ in ${\rm Sym}(H)$ by Cayley's Theorem, and this induces an embedding of $H$ into the simple group ${\rm Sym}(H)/K$, where $K$ consists of those permutation with support less than $\kappa$, which has cardinalty $2^\kappa$. So, the answer is yes if you assume GCH. Without that, it could be difficult.
Oct 30, 2015 at 10:10 comment added Derek Holt Every finite group is a subgroup of $A_n$ for all sufficiently large $n$ so it is certainly true that every finite simple group embeds properly in a larger one.
Oct 30, 2015 at 9:09 history edited Myshkin CC BY-SA 3.0
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Oct 30, 2015 at 8:58 history asked 喻 良 CC BY-SA 3.0