In the wee hours of Wednesday morning, IBM gave an unwary world its first publicly accessible quantum computer. You might be worried that you can tear up your passwords and throw away your encryption, for all is now lost. However, it's probably a bit early to call time on the world as we know it. You see, the whole computer is just five bits.
This might sound like some kind of publicity stunt; maybe it's IBM's way of clawing some attention back from D-Wave's quantum computing efforts. But a careful look shows that serious science undergirds the announcement.
The IBM system is, on a very superficial level, similar to D-Wave's. Both systems use superconducting quantum interference devices as qubits (quantum bits). But the similarity ends there. As IBM emphasizes, its quantum computer is a universal quantum computer—which D-Wave's is not.
Another big difference: IBM can address and measure the state of each qubit individually. The company can measure (and has) all the critical features of its device. If you want to know how long a qubit retains its state, IBM can tell you. IBM even shows that addressing multiple qubits in a random way doesn't affect the state of the others too badly. Big Blue is really building its quantum computer from the foundation up, while still ensuring that the engineering fits real-world requirements.
To read more, click here.