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How many functions can be distinguished with k quantum queries?

E. Farhi·J. Goldstone·S. Gutmann·M. Sipser
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Abstract

Suppose an oracle is known to hold one of a given set of D two-valued functions. To successfully identify which function the oracle holds with k classical queries, it must be the case that D is at most 2^k. In this paper we derive a bound for how many functions can be distinguished with k quantum queries.

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E. Farhi, J. Goldstone, S. Gutmann, M. Sipser. 1999-03-09. How many functions can be distinguished with k quantum queries?. https://doi.org/10.1103/physreva.60.4331

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