Twenty-year-old idea revealed the potential of quantum problem solving
A 20-year-old algorithm that demonstrated the benefit of using quantum mechanics to solve certain problems has finally been run on a quantum computer.
Simon’s algorithm, proposed by computer scientist Daniel Simon in 1994, provides instructions for a computer to determine whether a black box returns a distinct output for every possible input. It was the first example of problem-solving software that quantum computers should be able to execute exponentially faster than conventional computers as the problem gets harder.
Mark Tame, a physicist at the University of KwaZulu-Natal in Durban, South Africa, and colleagues report in the Nov. 14 Physical Review Letters that they ran a simple version of Simon’s algorithm on a computer with six quantum bits. The quantum computer ran the algorithm twice on average to solve the problem; a conventional computer would require nearly three tries on