Google Sycamore: Quantum Supremacy Claim
On October 23, 2019, Google Quantum AI published results in Nature claiming quantum supremacy. The Sycamore chip used 53 superconducting qubits to run a random circuit sampling task in about 200 seconds; the same task was estimated to take 10,000 years on the world's fastest supercomputer.
The milestone sparked debate over the definition of "supremacy" and the practical usefulness of the benchmark, but it marked a clear inflection point in public awareness of quantum computing progress.