Initial tests found that Google and Nasa’s quantum computing system was unable to outperform regular computers. But now Google has announced that its D-Wave computer has outperformed a traditional desktop by 108 times — making it one hundred million times faster.
“What a D-Wave does in a second would take a conventional computer 10,000 years to do,” said Hartmut Nevan, director of engineering at Google, during a news conference to announce the results.
The machine “raced” a conventional single-processor computer in a number of tasks, and outperformed it in every case, says Google. It has posted the results in a research paper, which is yet to be peer reviewed.
Google’s interest in the D-Wave machine, which has also been invested in by Microsoft and IBM, is due to the huge power quantum computers could potentially unlock. The so called “weirdness” of quantum mechanics — where the basic laws of physics break down — has the potential to solve long standing problems in in machine intelligence and materials science. On Nasa’s part, the computer could help schedule rocket launches or generate complex simulations of space missions.
Conventional computers encode data in binary code, made up of zeros and ones, and known as ‘bits’. But a quantum computer uses subatomic particles known as ‘qubits’, made up of zeroes, ones and a combination of the two known as a ‘superposition’. Where three bits can represent any one of eight values, three qubits can represent all eight values at once. This, in theory, allows quantum computers to run far faster than conventional computers.
The D-Wave machine is currently installed at the Ames Research Center in California, operating using a chip called a “quantum annealer”. The annealer uses an algorithm designed to solve so-called “optimisation problems” — essentially operational problems or questions common in artificially intelligent software. Thousands of binary variables are inputted into the machine before it works on problems.
The results are not a cut and dry victory for the machine, however. The D-Wave machine was specifically engineered to solve the problems faced by both computers, giving it a distinct advantage. And previous tests held with machines without this precise engineering found no significant difference between conventional computing and quantum computing.
Google is also working on other forms of quantum hardware, including some that isn’t limited to the optimisation problems the annealer is set to solve.
“While these results are intriguing and very encouraging,” Nevan said, “There is more work ahead to turn quantum enhanced optimisation into a practical technology”.