Let $V$ be a finite-dimensional complex inner product space and let $W$ be a subspace of $V$ such that $\dim V = 4$, $\dim W = 2$. Construct a linear operator $T$ such that
(i) $W$ is $T$-invariant and $T^{*}$ invariant
(ii) $T|_{W}$ is normal
(iii) $T$ is not normal.
Does it related to 'If $W$ is $T$ invariant then $W$ is $T^{*}$ invariant' ? Thank you.