Google’s announcement on Monday of its new quantum chip, called Willow, was full of eye-catching statements. For starters, Willow took less than a minute to perform a benchmark computation that would take one of today’s fastest supercomputers 10 septillion years to do. That number “exceeds known timescales and physics and vastly exceeds the age of the universe,” says Hartmut Neven, founder and lead at Google Quantum AI, in the announcement.
And then there’s error correction. “We achieved an exponential reduction in the error rate,” Neven says. In fact, the more physical qubits the team added, the more it reduced the error rate, hitting a historic accomplishment.
Since qubits – quantum bits – are notoriously unstable, quantum computer companies use redundancy to improve accuracy, with multiple physical qubits combining into a single “logical” qubit.
