In 1985 David Deutsch, at Oxford, publishes "Quantum Theory, the Church-Turing Principle and the Universal Quantum Computer", formalizing the first mathematical model of a universal quantum computer, building on Feynman (1981). He defines the quantum Turing machine, the qubit, and quantum gates, and proposes the first quantum algorithm with provable advantage over any classical algorithm (Deutsch's problem). This paper founds quantum computation theory, the basis for Shor (1994) and Grover (1996).