This event is a part of the Quantum Information Science and Technology (QuIST) Colloquium series. The talk will be held virtually on Zoom. 

Speaker: Andrew Childs, University of Maryland        

Title: Quantum Divide and Conquer

Abstract: The divide-and-conquer framework, used extensively in classical algorithm design, recursively breaks a problem into smaller subproblems, along with some auxiliary work, to give a recurrence relation for the classical complexity. We describe a quantum divide-and-conquer framework that, in certain cases, yields quantum speedup through an analogous recurrence relation for the quantum query complexity. We apply this framework to obtain near-optimal quantum query complexities for various string problems, such as (i) recognizing regular languages; (ii) decision versions of String Rotation and String Suffix; and natural parameterized versions of (iii) Longest Increasing Subsequence and (iv) Longest Common Subsequence.

* Based on joint work with Robin Kothari, Matt Kovacs-Deak, Aarthi Sundaram, and Daochen Wang.