Exploring Quantum Computing: Potential Applications and Current Challenges in Algorithm Design

Abstract

Quantum supremacy refers to the experimental demonstration that a quantum computing device performs a calculation that no classical computer can match in a reasonable time. Such machines would not be useful for solving problems of practical interest, but they would provide a proof of principle that larger and more useful machines could be built. The gap between classical and quantum computing is potentially enormous, and the apparent ease with which quantum states can be prepared, manipulated, and measured has led many to believe that quantum devices might one day outperform classical hardware at solving a broad range of computational tasks. The most immediate goal of progress in quantum engineering is the construction of a device that passes the proofs of principle of quantum supremacy experiments. They would transform a state that can be initialized neutrally, evolve it under a controlled Hamiltonian, then sample from the output distribution. Such devices must possess sufficient connectivity and low noise but can be cared for by classical software. Their demonstration would mark a historic milestone in the development of quantum technology, providing intrigue and awe but little societal benefit. However, if they can be produced with sufficient fidelity and scale, there is hope that more generally applicable quantum engines might be constructed that could exploit the exponential speedup to outperform classical computers for problems of deep societal importance.