closed subgroup theorem
... that John von Neumann's theorem that every closed real matrix group is a Lie group inspired Élie Cartan to prove a generali­za­tion, the closed subgroup theorem?
... that <a href="./John_von_Neumann" id="mwCc4" rel="mw:WikiLink" title="John von Neumann">John von Neumann</a>'s theorem that every closed real <a class="mw-redirect" href="./Matrix_group" id="mwCc8" rel="mw:WikiLink" title="Matrix group">matrix group</a> is a <a href="./Lie_group" id="mwCdA" rel="mw:WikiLink" title="Lie group">Lie group</a> inspired <a href="./Élie_Cartan" id="mwCdE" rel="mw:WikiLink" title="Élie Cartan">Élie Cartan</a> to prove a generali<span about="#mwt57" data-mw='{"parts":[{"template":{"target":{"wt":"shy","href":"./Template:Shy"},"params":{},"i":0}}]}' id="mwCdI" typeof="mw:Transclusion mw:Entity">­</span>za<span about="#mwt58" data-mw='{"parts":[{"template":{"target":{"wt":"shy","href":"./Template:Shy"},"params":{},"i":0}}]}' id="mwCdM" typeof="mw:Transclusion mw:Entity">­</span>tion, the <b id="mwCdQ"><a class="mw-redirect" href="./Closed_subgroup_theorem" id="mwCdU" rel="mw:WikiLink" title="Closed subgroup theorem">closed subgroup theorem</a></b>?