Qubit

The quantum state of a qubit is a vector of unit length in a 2dimensional complex vector space known as state space. It is typically represented as α0⟩ + β1⟩.

0⟩ and 1⟩ represent the two standard basis vectors of R^{2}.

unit length :: α^{2} + β^{2} = 1

complex vector space :: α and β can be complex numbers.


It is impossible to directly observe the state of a qubit.

When a qubit is measured, the qubit collapses to either 0⟩ or 1⟩ with probabilities α^{2} and β^{2} respectively.
 This is a fundamental consequence of physics. If this were not the case, infinite information could be encoded in a single qubit.