Quantum lower bound for inverting a permutation with advice

Given a random permutation as a black box and , we want to output . Supplementary to our input, we are given classical advice in the form of a pre-computed data structure; this advice can depend on the permutation but \emph{not} on the input . Classically, there is a data structure of size and an algorithm that with the help of the data structure, given , can invert in time , for every choice of parameters , , such that . We prove a quantum lower bound of for quantum algorithms that invert a random permutation on an fraction of inputs, where is the number of queries to and is the amount of advice. This answers an open question of De et al. We also give a quantum lower bound for the simpler but related Yao's box problem, which is the problem of recovering a bit , given the ability to query an -bit string at any index except the -th, and also given bits of advice that depend on but not on .
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