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Exact quantum query complexity for total Boolean functions

Gatis Midrijanis
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Abstract

We will show that if there exists a quantum query algorithm that exactly computes some total Boolean function f by making T queries, then there is a classical deterministic algorithm A that exactly computes f making O(T^3) queries. The best know bound previously was O(T^4) due to Beals et al.

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Gatis Midrijanis. 2004-03-27. Exact quantum query complexity for total Boolean functions. https://arxiv.org/abs/quant-ph/0403168

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