Quantum lower bounds by quantum arguments
Andris Ambainis · 2000
We propose a new method for proving lower bounds on quantum query algorithms.Instead of a classical adversary that runs the algorithm with one input and then modifies the input we use a quantum adversary that runs the input with a superposition of inputs.Using this method, we prove two new ~2(x/-N) lower bounds on AND of ORs and inverting a permutation and also provide more uniform proofs for some known lower bounds which have been previously proven via variety of different techniques.