**(PhysicsWorld)** Machine-learning algorithms have been run on a quantum computer by physicists at IBM. Although the proof-of-concept demonstration did not involve practical tasks, the team hopes that scaling-up the algorithms to run on larger quantum systems could give machine learning a boost. the IBM demonstrations were very basic. The team used two quantum bits (qubits) of IBM’s smallest commercial quantum computer – which has five superconducting qubits. This meant that that the quantum representation space only contained four dimensions.

Machine learning is a type of artificial intelligence that involves a computer working-out how to do a task by analysing large numbers of examples of the task being done. A typical task could be to tell the difference between photographs of cats and dogs. The machine learning system would be “trained” by inputting lots of images of cats and dogs and the system would create a mathematical model that has a clear boundary between cats and dogs.