Bloch sphere
Noun
Meaning
Bloch sphere (plural Bloch spheres)
(quantum mechanics) A geometrical representation of the pure state space of a two-level quantum-mechanical system, or qubit.
Examples
Because the absolute squares of the amplitudes equate to probabilities, it follows that α and β must be constrained by the equation : Bloch sphere The possible states for a single qubit can be visualised using a Bloch sphere (see diagram).
Mixed states can be represented by points inside the Bloch sphere.
Unitary transformations correspond to rotations of the qubit vector in the Bloch sphere.
When employing the Poincaré sphere (also known as the Bloch sphere ), the basis kets ( and ) must be assigned to opposing ( antipodal ) pairs of the kets listed above.