Separating vector for an operator algebra
= Separating vector for an operator algebra
{title2=$a\Omega=0\Longrightarrow a=0$}
= Separating vector
{synonym}
A <vector> is separating for an <operator algebra> when evaluation at that <vector> is injective. A cyclic <vector> for the <commutant of an operator algebra> is separating for the original algebra: if $a\Omega=0$, then $a$ vanishes on its dense commutant orbit.