“Quantum computers are starting to approach the limit of classical simulation”

In quantum computing the basic variable that holds information is known as a qubit. Qubits un cannot be represented like classical bits as they obey the laws of quantum mechanics.

We can visualise a single qubit using the Bloch Sphere, which is a geometrical representation. By using the two variables pheta and phi we can represent each possible qubit state as a point on the surface of a bloch sphere.

Quantum Superposition - When any two or more quantum states can be superposed and the result is another valid quantum state

Quantum superposition can also be represented by the Schrödinger equation

The complex conjugate is a complex number that has been reflected in the real axis (the real and imaginary parts are equal but the sign of the imaginary part reversed).