The Quantum House Of Cards

Abstract

Quantum computers have been proposed to solve a number of important problems such as discovering new drugs, new catalysts for fertilizer production, breaking encryption protocols, optimizing financial portfolios, or implementing new artificial intelligence applications. Yet, to date, a simple task such as multiplying 3 by 5 is beyond existing quantum hardware. This article examines the difficulties that would need to be solved for quantum computers to live up to their promises. I discuss the whole stack of technologies that has been envisioned to build a quantum computer from the top layers (the actual algorithms and associated applications) down to the very bottom ones (the quantum hardware, its control electronics, cryogeny, etc.) while not forgetting the crucial intermediate layer of quantum error correction.

7 pages, 1 figure. Published as a Perspective in PNAS

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Cited by in corpus (5)

• Engineering of Anyons on M5-Probes via Flux Quantization
• Simulating Quantum Circuits with Tree Tensor Networks using Density-Matrix Renormalization Group Algorithm
• Feasibility of performing quantum chemistry calculations on quantum computers
• Limits of Clifford Disentangling in Tensor Network States
• Who can compete with quantum computers? Lecture notes on quantum inspired tensor networks computational techniques