On quantum generalization of the Church-Turing universality of computation
نویسنده
چکیده
In classical computation, any computable function can be computed by a universal Turing machine, and the program is independent of the value of the variable. Trying to generalize this universality to quantum computation, one anticipates that there is a universal quantum Turing machine which can perform any desired unitary transformation on an arbitrary number of qubits, by including a program as another part of the input state; or the program effecting a unitary transformation is independent of the state of qubits to be computed. It is shown, however, due to entanglement, neither of these two situations exists in Deutsch’s quantum Turing machine. The discussion improves the understanding of a puzzle about halt scheme or synchronization of computational paths. PACS numbers: 89.70.+c, 03.65.-w Typeset using REVTEX
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