Please note: This master’s thesis presentation will be given online.
Rory Soiffer, Master’s candidate
David R. Cheriton School of Computer Science
Supervisor: Professor Shalev Ben-David
Quantum query complexity measures the minimum number of queries a quantum algorithm needs to make to some input string to compute a function of that input. Query complexity models are widely used throughout quantum computing, from setting limits on quantum algorithms to analyzing post-quantum cryptography.
This thesis studies quantum adversary methods, a group of mathematical tools that prove lower bounds on quantum query complexity. I introduce a new general-purpose framework for adversary methods that generalizes over both the negative weight and multiplicative adversary methods. This framework unifies the lower bound proofs of both methods, even in the general case of quantum state conversion.
This generalized method also gives a new formula for the multiplicative adversary method based on max-relative entropy. This new definition is more concise and easier to reason about than existing definitions in the literature. I verify this by reproving several known results about the multiplicative adversary method. I also use this to reprove the strong direct product theorem for quantum query complexity.
To join this master’s thesis presentation on Zoom, please go to https://uwaterloo.zoom.us/j/96370886320.
200 University Avenue West
Waterloo, ON N2L 3G1