Breakthrough in Quantum Computing: Challenges and Opportunities for Blockchain from Google's Chip Willow

Google's latest quantum computing chip, Willow, has once again sparked industry attention on the development of quantum computing. This chip, which has 105 qubits, has achieved best-in-class performance in two benchmark tests: quantum error correction and random circuit sampling. Notably, in the random circuit sampling test, Willow completed a computational task in just 5 minutes that would take a traditional supercomputer 10^25 years to accomplish, a timespan that even exceeds the age of the known universe.

An important breakthrough of Willow is its ability to achieve an exponential reduction in error rates and keep them below a specific threshold, which is considered a key prerequisite for achieving large-scale practical Quantum Computing. Hartmut Neven, the head of the research and development team, stated that Willow is the first system to operate below the threshold, demonstrating the feasibility of large-scale practical quantum computers.

Although Willow's 105 qubits are still far from sufficient to crack the cryptographic algorithms used in current cryptocurrencies, it paves the way for the future development of more powerful quantum computers. This undoubtedly poses a potential challenge for the blockchain and cryptocurrency sectors that rely on existing cryptographic principles.

Currently, cryptocurrencies such as Bitcoin widely use the Elliptic Curve Digital Signature Algorithm ( ECDSA ) and SHA-256 hash function to ensure transaction security. Although it takes hundreds of millions of quantum bits to crack SHA-256, theoretically, using Shor's quantum algorithm could crack ECDSA with only millions of quantum bits. This means that once large-scale quantum computers become available, the existing cryptocurrency security system may face serious threats.

In response to this challenge, developing quantum-resistant Blockchain technology, especially upgrading existing Blockchain to be quantum-resistant, has become a top priority. Post-quantum cryptography (PQC), as a type of new cryptographic algorithm capable of resisting quantum computing attacks, is becoming a research hotspot. Some technical teams have made progress in this area, including completing the construction of post-quantum cryptography capabilities for the entire Blockchain process, developing an improved OpenSSL cryptographic library that supports multiple NIST standard post-quantum cryptographic algorithms, and researching distributed key management protocols for NIST post-quantum signature standard algorithms.

Although migrating blockchain to a quantum-resistant level still faces many technical challenges, such as the storage expansion issue of post-quantum signatures compared to ECDSA, some teams have already optimized the consensus process and reduced memory read latency, allowing quantum-resistant blockchain transaction processing speeds to reach about 50% of the original chain at ( TPS ). These advancements provide important guarantees for the security and stability of blockchain in the quantum era.

The advancement of Quantum Computing is both a challenge and an opportunity. It drives innovation in cryptography and Blockchain technology, prompting the industry to pay more attention to long-term security. As research progresses, we have reason to believe that Blockchain technology will continue to play an important role in the future quantum era.