Question: I saw another post on Quantum computers and i was wondering on how you think they work and I know they have already been commercialized but do you ever think they will be used for home use? Also how many qubits do you think the early quantum computers will have??

Steven Thomson answered on 15 Jun 2015:

Quantum computers work by using quantum bits (qubits) to do computations on rather than classical bits like in a normal computers. Qubits are really neat because they can be in more than one state at a time, whereas normal bits are either 0 or 1. This means qubits can do multiple things at once, meaning when you string together lots of qubits, you can a massive speed increase over normal computers.

There’s only one commercial one, the D-Wave, but it’s not a ‘true’ quantum computer. Proper ones don’t exist yet, and most prototypes only have around 10 qubits or so.