ITEM: Three years ago, Google’s Sycamore quantum computer solved a problem no ordinary computer could do. Now an ordinary computer has solved it via a clever new algorithm.
In 2019, Sycamore performed a task that involves verifying that a sample of numbers output by a quantum circuit have a truly random distribution. Google claimed that the world’s most powerful supercomputer at that time, IBM’s Summit, would take 10,000 years to solve this particular task – Sycamore did it in 3 minutes and 20 seconds.
Google declared that Sycamore had achieved “quantum supremacy by doing something that only a-quantum computer could do. However, a team at the Chinese Academy of Sciences in Beijing says they’ve created an algorithm that allows a non-quantum computer to solve the same task.
New Scientist reports:
The researchers found that they could skip some of the calculations without affecting the final output, which dramatically reduces the computational requirements compared with the previous best algorithms.
The researchers ran their algorithm on a cluster of 512 GPUs (graphics processing units), completing the task in around 15 hours.
That’s not quite as fast as Sycamore. But it’s a lot shorter than the 10,000 years Google claimed it would take a cutting-edge supercomputer to do. The researchers noted that the algorithm could beat Sycamore’s time by running it on an exascale computer. That said, such computers are rare, and require a lot of performance overhead.
Quantum computing will win eventually
While the results are impressive on paper, they don’t spell doom for Sycamore or quantum computing in general. One expert notes that the algorithm pits modern exascale computing with quantum computer technology from three years ago.
Quantum computing has made considerable progress since then – and Sergio Boixo, principal scientist at Google Quantum AI, pointed out in a statement that quantum technology “improves exponentially faster” than classical computing:
“… So we don’t think this classical approach can keep up with quantum circuits in 2022 and beyond, despite significant improvements in the last few years.”
Research leader Pan Zhang agrees that classical computers are unlikely to keep pace with quantum machines for certain tasks, according to New Scientist:
“Eventually quantum computers will display overwhelming advantages over classical computing in solving specific problems,” he says.
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