MilestoneQuantum advantageDisputed
Google claims quantum supremacy with its 53-qubit Sycamore processor
Oct 23, 2019
Google researchers report in Nature that their Sycamore superconducting processor, using 53 qubits, sampled the output of a random quantum circuit a million times in about 200 seconds, a task they estimated would take a state-of-the-art supercomputer about 10,000 years.
Why it matters
Google called it the first quantum computation that cannot reasonably be emulated on a classical computer. The task had no practical use; it was chosen as a demanding benchmark of the hardware.
IBM praised the hardware but argued an ideal classical simulation could do the task in about 2.5 days, not 10,000 years. In 2021 Pan, Chen and Zhang generated a million samples from the same 53-qubit circuits in about 15 hours on 512 GPUs, so how far the chip outran classical computers is contested.
John Martinis · Sergio Boixo · Google · NASA
Related
Sources (5)
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Nature
Quantum supremacy using a programmable superconducting processor
“Our Sycamore processor takes about 200 seconds to sample one instance of a quantum circuit a million times—our benchmarks currently indicate that the equivalent task for a state-of-the-art classical supercomputer would take approximately 10,000 years.”
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Google Research Blog
Quantum Supremacy Using a Programmable Superconducting Processor
“With the first quantum computation that cannot reasonably be emulated on a classical computer, we have opened up a new realm of computing to be explored.”
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Nature News
Hello quantum world! Google publishes landmark quantum supremacy claim
“The company says that its quantum computer is the first to perform a calculation that would be practically impossible for a classical machine.”
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IBM Research Blog
On "quantum supremacy"
“We argue that an ideal simulation of the same task can be performed on a classical system in 2.5 days and with far greater fidelity.”
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arXiv (Pan, Chen and Zhang)
Solving the sampling problem of the Sycamore quantum circuits
“If our algorithm could be implemented with high efficiency on a modern supercomputer with ExaFLOPS performance, we estimate that ideally, the simulation would cost a few dozens of seconds, which is faster than Google's quantum hardware.”
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