Quantum Computing for the Curious

In 1985, the English physicist David Deutsch suggested a deeper approach to the problem of defining what is meant by an algorithmDavid Deutsch, “Quantum theory, the Church-Turing principle and the universal quantum computer” (1985). Deutsch pointed out that every algorithm is carried out by a physical system, whether it be a mathematician with paper-and-pencil, a mechanical system such as an abacus, or a modern computer. And in trying to answer his question, Deutsch observed that ordinary, everyday computers based on Turing’s model have a lot of trouble simulating quantum mechanical systemsResearchers such as Yu Manin and Richard Feynman had previously observed this, and as a result had speculated about computers based on quantum mechanics.

Source: quantum.country