Classical computers that we use today have bits that can be either 0 or 1 (like a light switch: on or off) and these can be used to store numbers and pictures. Quantum computers have bits called qubits which can be 0 or 1 at the same time. Whereas a classical computer bit can only represent two states 0 or 1; a quantum computer qubit can represent four states: 00, 01, 10, and 11.
|1 bit||2 to the power 1 = 2 representations (0, 1)|
|1 qubit bit||2 to the power 2 = 4 representations (00, 01, 10, 11)|
|2 bits||2 to the power 2 = 4 representations (00, 01, 10, 11)|
|2 qubit bits||2 to the power 4 = 16 representations (0000, .... 1111)|
|3 bits||2 to the power 3 = 8 representations (000, 001, 010, 011, 100, 101, 110, 111)|
|3 qubit bits||2 to the power 8 = 256 representations (00000000, .... 11111111)|
As you can see above, the quantum computer representations rise exponentially so that a mere 305 qubits, which is equal to the information capacity of the observable universe, would require 2 to the power 305 classical bits and therefore this would be impossible on a classical computer!
There is a catch to using qubits for computing and this is the requirement that qubits need to be entangled to be meaningful. Particles become entangled, when they are created together. When entangled particles are not observed, they have no state. Particles that are entangled have the property that no matter how far away they are from each other, when observed they take opposite states. Einstein thought that this was not possible and thus he called it "spooky action at a distance". However, it has been proved to be true.
The state of superposition, having two states at the same time, until they are observed, represents the third state of matter on the quantum level. The three states can be expressed as positive, negative, and neutral or as Gurdjieff called them: active, passive and neutralizing. Thus Quantum Mechanics confirms the amazing fact that "observation", when in a state of impartiality (the neutral state: Kesdjanian/Astral Body), creates the distinction between active force (the Soul) and passive force (the Body). It is only through observation of this neutral state that growth is possible.
Beelzebub's Tales to His Grandson