Experimental Evidence Confirms That D-Wave Systems' Quantum Computers Are Truly 'Quantum'

"The important thing to realize is that we're demonstrating quantum entanglement in an operational computer, not some lab experiment," said Colin Williams. "It's a computer running software you'd be familiar with."

Williams is Director of Business Development at quantum computing company D-Wave Systems, as well as an author, researcher, and noted thinker in the field in his own right.

There's been a fair bit of quibbling among physics professionals as to whether D-Wave's computers are truly "quantum," but experimental evidence discussed in a new paper seals the deal: D-Wave's computers are so quantum that they display "entanglement," a weird characteristic of the subatomic world in which pairs of particles become "related" to each other - changing one of them instantly changes the other, even though they're separated by some distance.

"For the longest time people said entanglement was the gold standard - 'Until you show this, you don't have a quantum computer.' So this is a major step for the field as a whole," said Williams. "I like to describe it in the context of the memory register of a [classical] computer. Whatever operation you perform doesn't have a side effect on the bits you don't touch, but quantum bits affect each other even though you didn't touch them."

Quantum computers are those that draw their computational power from the quirks of the quantum world. Rather than using classical computer bits, which represent either a one or a zero and enable every single thing your computer does today, they use quantum bits (called qubits) that can represent a one, zero, or any value in between, all at once. This key difference grants quantum computers staggering capabilities to solve some of the stupid-hardest problems that would stump other computers.

A qubit's ability to represent multiple values at the same time sounds counterintuitive, but it's completely scientific. The subatomic world plays by rules that are totally alien to us - particles disappear and reappear in different places, the same particle might exist in multiple places simultaneously, and it's hypothesized that quantum entanglement might soon have us sending and receiving information instantaneously across any distance. A qubit's curious properties are simply an extension of these quantum quirks.

Quantum computers will prove themselves most useful in the arena of optimization. The go-to example of an optimization problem is that of a hypothetical traveling salesman who needs to visit several cities while traveling as short a distance as possible. Classical non-quantum computers can solve this quite inefficiently by way of brute force, chugging away for the optimal solution by manually checking every possible route configuration, then returning the shortest one. But a quantum computer can solve this problem as operationally as you might solve a basic addition problem - some speculate that the reason for this computational ease is because quantum computers are running calculations in alternate universes (!!!).

Many fields need new ways of solving optimization problems. In pharmacology, researchers need to find drugs that can best bond with a complex molecule. With regard to artificial intelligence, a robot planning its path around a room is simply engaging in an optimization problem.

As Williams puts it, D-Wave is "tapping into the fabric of reality to use quantum physical effects to computer in new ways." Now that the company's computers exhibit entanglement, it dramatically shortens the amount of time needed before quantum computing makes an impact on our lives.