Optimal quantum query bounds for almost all Boolean functions
نویسندگان
چکیده
We show that almost all n-bit Boolean functions have bounded-error quantum query complexity at least n/2, up to lower-order terms. This improves over an earlier n/4 lower bound of Ambainis [1], and shows that van Dam’s oracle interrogation [9] is essentially optimal for almost all functions. Our proof uses the fact that the acceptance probability of a T -query algorithm can be written as the sum of squares of degree-T polynomials. 1998 ACM Subject Classification F.1.1 Models of Computation
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تاریخ انتشار 2013