Quantum supremacy is the purpose of demonstrating {that a} quantum laptop can remedy an issue that no classical laptop can remedy in any possible period of time, no matter the usefulness of the issue. This idea was coined by John Preskill in 2012, however the concept dates again to the Eighties when Yuri Manin and Richard Feynman proposed quantum computing.
Quantum supremacy is just not solely a scientific problem, but additionally an engineering one. It requires constructing a robust quantum laptop and discovering an acceptable drawback that may exploit the quantum benefit over classical algorithms . Some examples of such issues are boson sampling, annoyed cluster loop issues, and random quantum circuit sampling.
In 2019, Google claimed to have achieved quantum supremacy through the use of a 53-qubit processor referred to as Sycamore to carry out a random quantum circuit sampling activity in 200 seconds, which they estimated would take probably the most superior supercomputer 10,000 years to do . This outcome was printed in Nature and verified by NASA and Oak Ridge Nationwide Laboratory . Nevertheless, this declare was disputed by IBM, which argued that the identical activity could possibly be performed by a classical supercomputer in 2.5 days with some optimizations.
Since then, different teams have additionally reported reaching quantum supremacy or quantum benefit utilizing completely different platforms and issues. For instance, in 2020, a workforce from China used a photonic quantum laptop with 76 photons to carry out Gaussian boson sampling, which they claimed would take a classical supercomputer 600 million years to do. In 2021, a workforce from France used an analog quantum simulator with 51 superconducting qubits to simulate the dynamics of quantum magnets, which they claimed would take a classical supercomputer greater than a century to do.
These achievements are spectacular, however they aren’t but sensible or helpful for real-world functions. They’re primarily proofs of idea that exhibit the potential of quantum computing. To comprehend this potential, many challenges stay, resembling scaling up the quantity and high quality of qubits, implementing error correction and fault tolerance, creating environment friendly algorithms and software program, and discovering related issues that may profit from quantum speedup.
Quantum supremacy is just not a set or last purpose, however a transferring goal that is dependent upon the state-of-the-art of each quantum and classical computing. Additionally it is not a binary or absolute idea, however a relative and gradual one which is dependent upon the issue and the sources out there. It’s doable that quantum supremacy could also be non permanent or unstable, as classical computer systems and algorithms might catch up or surpass quantum ones in some circumstances.
Due to this fact, quantum supremacy shouldn’t be seen as an finish in itself, however as a milestone alongside the way in which to quantum benefit, which is the flexibility to make use of quantum computer systems to resolve issues that aren’t solely arduous for classical computer systems, but additionally significant and useful for science, trade, and society.