Fast quantum algorithm for numerical gradient estimation.
نویسنده
چکیده
Given a black box for f, a smooth real scalar function of d real variables, one wants to estimate [symbol: see text]f at a given point with n bits of precision. On a classical computer this requires a minimum of d + 1 black box queries, whereas on a quantum computer it requires only one query regardless of d. The number of bits of precision to which f must be evaluated matches the classical requirement in the limit of large n.
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عنوان ژورنال:
- Physical review letters
دوره 95 5 شماره
صفحات -
تاریخ انتشار 2005