Reflection operator
= Reflection operator
For a unit vector $|\psi\rangle$, the reflection $I-2|\psi\rangle\langle\psi|$ negates the component parallel to $|\psi\rangle$ and fixes its orthogonal complement.
= Reflection operator
For a unit vector $|\psi\rangle$, the reflection $I-2|\psi\rangle\langle\psi|$ negates the component parallel to $|\psi\rangle$ and fixes its orthogonal complement.