Quantum computers are again drawing attention for the possibility they could reach a practical level within the next 10 years. In particular, as progress appears in error-correction technology and the implementation of logical qubits—long seen as the biggest challenges in quantum-computer development—interest is also rising in Bitcoin’s long-term cryptographic security.

Bitcoin Magazine reported on Tuesday that technology in the quantum-computing industry has recently been advancing to reduce errors while increasing the number of physical qubits. This has made the possibility of a working quantum computer within the next 10 years a more realistic scenario than before.

The key issue is not the performance of quantum computers themselves, but how effectively errors can be controlled. Because quantum computers are highly sensitive to external noise, current technology requires bundling multiple physical qubits to create a stable logical qubit. Under existing surface-code methods, needing several hundred to nearly 1,000 physical qubits to implement a single logical qubit has been cited as a major limitation.

Quantum low-density parity-check (qLDPC) codes are drawing attention as a way to reduce this bottleneck. qLDPC is designed to check errors even between qubits that are far apart, aiming to sharply reduce the number of physical qubits needed to create a stable logical qubit compared with existing methods. The outlet said this should not be equated with the arrival of a completed quantum computer, but it is a sign that engineering efficiency for building large-scale quantum systems is improving.

Google experiments are also notable. Google tested whether logical error rates fall as the number of physical qubits increases using its Sycamore and Willow chips. In experiments using 17, 49 and 101 physical qubits, it presented results showing that logical error rates declined as the qubit scale increased.

Still, the experiment should not be interpreted to mean a fully fledged quantum computer has arrived. The study did not perform calculations impossible for classical computers, but focused on whether quantum information could be stored stably for a certain period. In particular, it highlighted as an important achievement that the logical qubit passed a threshold where it maintained coherence longer than the individual physical qubits that make it up.

Artificial intelligence (AI) is also being cited as a factor that could speed up quantum-computer development. AI is being used not only to develop quantum algorithms but also to design actual circuits and optimise qubit placement. Because calculating how to arrange quantum gates to reduce noise and latency is complex, the explanation is that AI-driven design automation could improve development efficiency.

The most sensitive part of the Bitcoin network is the long-term threat to its cryptographic system. If a sufficiently powerful quantum computer emerges, some of the current encryption methods could be vulnerable to attack. Concerns have steadily been raised that Bitcoin’s public-key cryptography could become a target for quantum computers over the long term.

That does not mean today’s quantum computers have reached a level where they can decrypt Bitcoin’s cryptography. For an actual threat to materialise, it would be necessary to stably operate large-scale logical qubits while controlling errors and to perform the calculations needed for decryption. Current technology is still far from that stage.

Ultimately, the core of this discussion is not whether Bitcoin can be breached by quantum computers right away, but whether cryptographic technology can keep pace with the speed of quantum-computer advances. If error correction and logical-qubit technology progresses faster than expected, the time needed to prepare a shift to quantum-resistant cryptography becomes that much more important.

Bitcoin Magazine also stressed that, while guarding against excessive fear, the potential for quantum-computer advances should not be ignored. There is no immediate threat to the Bitcoin network yet, but discussions on shifting cryptographic technology to prepare for quantum computers are expected to become more important as a long-term security task over the next 10 years.