On methods of calculation of π on quantum computers

Abstract

A simple one-qubit algorithm to compute π is considered and compared to another algorithm proposed by Noto with respect to the precision offered and its quantum computation requirements. We find that π = 3:157±0:017 with our algorithm on a real quantum computer and that Noto's algorithm offers accuracy comparable to that, but only on a simulator; heavy use of two-qubit gates would cause Noto's proposed algorithm for calculation of π to perform much worse on quantum computers currently publicly available.