Firmly nonexpansive mapping
= Firmly nonexpansive mapping
= Firmly nonexpansive
{synonym}
A mapping $T$ on an <inner product space> is firmly nonexpansive when
$$
\|T(v)-T(w)\|^2
\leq\langle T(v)-T(w),v-w\rangle.
$$
Every firmly nonexpansive mapping is <nonexpansive>, and the resolvent of a maximal <monotone operator> is firmly nonexpansive.