This section explores the simplest case of quantum measurement, focusing on states that are eigenvectors of the observable and do not involve superposition. The Quantum Axioms discussed earlier are particularly relevant here.

In this section, we cover:

C²  quantum states (two-dimensional complex vector space),

C²  ⊗ C²  quantum states (tensor product of two C² ),

C²  ⊗ C²  ⊗ C²  quantum states (tensor product of three C²), and

The generalization of ⊗ⁿC²  (the tensor product of nC²).