Quantum supremacy refers to the point at which a quantum computer can solve a specific computational problem that is beyond the capabilities of the most powerful classical computers. It represents a milestone in the development of quantum computing, demonstrating its potential to perform calculations that are practically infeasible for classical computers.
The term "quantum supremacy" was coined by John Preskill, a theoretical physicist at the California Institute of Technology, in 2012. It signifies a clear advantage of quantum computers over classical computers for a particular task.
To achieve quantum supremacy, a quantum computer must perform a computation that is exponentially faster than any known classical algorithm for the same problem. This typically involves demonstrating a quantum algorithm that solves a problem in a time complexity that scales better than any known classical algorithm. The specific problem chosen for demonstrating quantum supremacy should be carefully selected to highlight the strengths of quantum computing and be difficult for classical computers to solve efficiently.
In 2019, Google's research team claimed to have achieved quantum supremacy by performing a calculation on their quantum processor that would have taken thousands of years for the most powerful classical supercomputers to complete. This achievement marked an important milestone in the field of quantum computing and sparked increased interest and investment in quantum technologies.
It's worth noting that quantum supremacy does not imply that quantum computers are universally superior to classical computers for all types of computations. Classical computers still excel in many areas and are more efficient for most everyday computing tasks. However, quantum supremacy demonstrates the potential for quantum computers to tackle certain problems that are intractable for classical systems, opening up new possibilities for solving complex scientific, mathematical, and optimization problems.