When will quantum computers beat classical computers?

2025-12-18 · Source: IBM Research · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Emerging Technologies & Innovation, Quantum Computing · Depth: Intermediate, extended

Summary

IBM Quantum's Abhinav Khandala discusses the concept of "quantum advantage," defining it as quantum hardware outperforming classical methods in efficiency, cost, or accuracy, coupled with rigorous validation of results. He emphasizes that quantum advantage does not immediately imply "usefulness" in a commercial sense, but rather a scientific milestone. Khandala outlines three categories for rigorously demonstrating quantum outperformance: problems with efficient classical verification (e.g., peaked circuits), problems with variational solutions for finding ground states, and observable estimations using error mitigation techniques. He highlights the critical need for quantum computers to scale beyond 100 qubits and achieve significantly lower error rates, noting a recent 10x improvement from 1% to 0.1% median error rates. The discussion also introduces the Quantum Advantage Tracker, a public, community-driven platform designed to accelerate the benchmarking and validation of quantum and classical computational methods in real-time.

Key takeaway

For AI Scientists focused on quantum computing's practical applications, understanding the nuanced definition of quantum advantage is crucial. Focus on contributing to the Quantum Advantage Tracker by proposing challenging problems or benchmarking existing quantum circuits against state-of-the-art classical methods. This collaborative, open-science approach will accelerate the identification of specific circuits and parameters where quantum-classical hybrid systems demonstrably outperform classical-only solutions, paving the way for future "killer apps" beyond current thousands-of-gate limitations.

Key insights

Quantum advantage requires rigorous validation of quantum outperformance over classical methods, not just raw computational power.

Principles

• Quantum advantage is a scientific milestone, not immediate commercial utility.
• Error mitigation is crucial for near-term quantum utility.
• Community collaboration accelerates quantum advantage discovery.

Method

Quantum advantage is rigorously demonstrated through three problem categories: efficient classical verification, variational solutions for ground states, and observable estimations with error bounds, often integrating classical HPC.

In practice

• Explore peaked circuits for quantum verification benchmarks.
• Utilize variational methods for approximating ground states.
• Apply error mitigation to extract accurate observable estimations.

Topics

• Quantum Advantage
• Quantum Computing Validation
• Error Mitigation
• Quantum-Centric Supercomputing
• Quantum Advantage Tracker

Best for: AI Scientist, AI Researcher, Research Scientist, Domain Expert

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Editorial summary, takeaway, and curation by AIssential. Original article published by IBM Research.