Forecasting timelines of quantum computing

TL;DR

This paper forecasts quantum computing progress by analyzing system data, modeling future improvements, and estimating timelines for fault-tolerant and RSA-2048 factoring capabilities.

Contribution

It introduces a dataset of quantum systems, defines a generalized logical qubit metric, and applies regression models to predict future quantum computing milestones.

Findings

Fault-tolerant quantum computing unlikely before 2026

RSA-2048 factoring unlikely before 2039

Progress may accelerate if current exponential trends continue

Abstract

We consider how to forecast progress in the domain of quantum computing. For this purpose we collect a dataset of quantum computer systems to date, scored on their physical qubits and gate error rate, and we define an index combining both metrics, the generalized logical qubit. We study the relationship between physical qubits and gate error rate, and tentatively conclude that they are positively correlated (albeit with some room for doubt), indicating a frontier of development that trades-off between them. We also apply a log-linear regression on the metrics to provide a tentative upper bound on how much progress can be expected over time. Within the (generally optimistic) assumptions of our model, including the key assumption that exponential progress in qubit count and gate fidelity will continue, we estimate that that proof-of-concept fault-tolerant computation based on superconductor technology is unlikely (<5% confidence) to be exhibited before 2026, and that quantum devices capable of factoring RSA-2048 are unlikely (<5% confidence) to exist before 2039. It is of course possible that these milestones will in fact be reached earlier, but that this would require faster progress than has yet been seen.