Metamorphic testing of oracle quantum programs

Abstract

Quantum Computing is regarded with a growing sense of excitement and expectation. While the preliminary evidences of its practical interest accumulate, there are numerous challenges that must be addressed before quantum computing can reach generalized adoption and realize its full potential. One such challenge concerns assessing whether a quantum program is correct, namely in the sense that it implements the desired functionality. In the classical realm, program testing is a well-established approach to find defects in programs. While this approach should inspire quantum software development, porting classical testing techniques to the quantum world is by no means trivial. We propose a novel approach to test quantum programs. Our approach is based on the use of metamorphic relations, which allows us to overcome the well-known quantum measurement problem. We describe a series of exploratory experiments whose results provide evidence of the usefulness of our approach.