Bristol University, a university with a proud science heritage that includes educating quantum physics pioneer Paul Dirac, has a center for quantum photonics...and here they keep a two qubit device. This is an honest-to-goodness experimental quantum computer, and instead of keeping it to themselves the university has created "Qcloud," a public access web portal that lets anyone from scientists to school kids to try out the technology.
Lest you forget, almost every single computer running in the world today runs on more or less unsurprising digital electronic principles, flipping an extraordinary number of bits of data around its circuits--obeying pretty mundane laws of physics. The bits are made of pulses of electrical current, symbolizing the binary states "1" and "0," and faster computers simply shuttle more pulses around at a faster rate. Though there are some revolutions going on in post-silicon chip technology, pretty much every computer will operate on this principle for a while.
But quantum computing is a wholly different and rather more excitingly weird thing. Instead of storing information in digital electrical bits, quantum computers use the freaky common sense-defying laws of quantum physics to store information in qubits. A qubit, or quantum bit, is similar to a digital bit in that it has a 0 state and a 1 state, but unlike a regular bit a qubit can be in one state, the other state, or both at once at the same time. Think less like a light switch and more of the famous Schrodinger's Cat experiment, and you're getting closer to what a qubit is.
Quantum computing, which is literally computing with quantum bits, is very much in its infancy. But the bizarre fact that qubits can be both on and off at the same time means that near future quantum computers could have fantastic power...like solving algorithms that would take today's supercomputers an impossibly long time to do, or taking on number-crunching tasks so frighteningly vast that we simply couldn't afford to build a digital computer to perform the same calculations. Quantum computing could be one route to creating really unbreakable cryptography or even more realistic artificial intelligent systems, for example.
Instead of retiring the two-qubit chip they built in 2011, the decision by the university to put the device online seems to have borrowed some of the thinking "maker" trend, and it's being described by the team behind it as the "Raspberry Pi of quantum computing." Not everyone will get to run algorithms through the chip at first, and there's a complex simulation built into the software that users try their code out on first. But the educational value of the idea, and perhaps even the potential for some real ground-breaking discoveries, can't be denied.
[Image: Flickr user Francesca Barone]