Google Issues Warning: Cryptocurrency Industry Must Transition to Post-Quantum Cryptography

Original Title: Google Urges Cryptocurrency Community to Transition to Post-Quantum Cryptography
Original Author: QuantumZeitgeist
Translation: Peggy, BlockBeats

Editor's Note: While quantum computing is still considered a "long-term risk," Google's latest research provides a more imminent signal: the attack threshold is rapidly decreasing, and the security perimeter is also tightening ahead of schedule.

According to Google, the quantum threat is no longer just a technical issue but a systemic transition that needs to be planned in advance. For the encryption industry, the real challenge is no longer "whether it will happen" but whether it can complete the transition to post-quantum cryptographic systems before the risk materializes.

The following is the original article:

Google is urging the cryptocurrency community to transition to post-quantum cryptographic systems as soon as possible and has pointed out in its latest research that facing future quantum computers, the resources required to break existing security mechanisms may be much lower than previously expected in the market.

In a newly published whitepaper, Google Quantum AI reassessed the quantum computing resources required to break the elliptic curve cryptography (ECC) that underpins most blockchain and security systems. The results show that this process may only require fewer than 500,000 physical quantum bits. The research team also built a quantum circuit scheme to execute the Shor algorithm to break ECDLP-256, requiring only about 1450 logical qubits and 70 million Toffoli gates, compressing the required scale of physical qubits to about one-twentieth of the previous estimate.

Quantum Algorithm Lead Ryan Babbush and Engineering Vice President Hartmut Neven stated that this action is aimed at raising industry awareness of this issue and providing specific recommendations to the encryption community to complete the security system's transition and upgrade before relevant threats materialize.

Google Provides a Post-Quantum Cryptographic Migration Timeline: Key Milestone in 2029

Google is actively addressing an approaching digital security risk—the potential for quantum computers to break existing mainstream encryption standards. The latest research from Google Quantum AI team shows that the resources required for future quantum computers to break the elliptic curve cryptography used to protect cryptocurrency systems may be significantly lower than previously expected, prompting the company to adopt a more proactive response strategy.

This research provides a more refined calculation of the attack cost by quantifying the quantum resources (including qubits and gate operations) needed to break the 256-bit elliptic curve discrete logarithm problem (the core foundation of the current cryptographic system)—the required physical qubit scale has decreased by approximately 20 times from previous estimates, reflecting a significant improvement in algorithm efficiency. Based on this, Google has proposed a migration path with 2029 as a milestone and is collaborating with institutions such as Coinbase, the Stanford Blockchain Research Center, and the Ethereum Foundation to advance the groundwork for a systematic transition to ensure the long-term stable operation of the cryptocurrency asset system.

Latest Estimate of Shor's Algorithm: About 1200 Quantum Bits and 70 Million Toffoli Gates

Recent advances in quantum computing are forcing the industry to reassess the resource requirements for breaking existing encryption schemes, especially the security foundations of cryptocurrencies. Researchers from Google Quantum AI have updated the execution cost estimate of Shor's algorithm in a whitepaper. This algorithm theoretically can break the elliptic curve cryptography used to secure digital assets. The results show that the required quantum bits and gate operations for this attack are significantly lower than previously estimated. According to their calculations, under current hardware assumptions, these quantum circuits can run to completion in minutes on a superconducting quantum computer with fewer than 500,000 physical quantum bits. This optimization reduces the physical quantum bit requirement for breaking ECDLP-256 by about 20 times and continues the ongoing improvement path of quantum algorithms in compilation and efficiency.

To responsibly disclose these findings, Google has engaged with the U.S. government and developed a "zero-knowledge proof" mechanism to allow external parties to verify the correctness of their research conclusions while avoiding directly providing an attack blueprint. The researchers suggest that blockchain systems should gradually transition to post-quantum cryptography with resistance to quantum attacks and call on other research teams to adopt similar responsible disclosure methods to protect user security.

Zero-Knowledge Proof: Seeking the Boundary Between Transparency and Security

Google researchers are exploring a new secure disclosure method to address the unique challenge posed by quantum computing. The core of this approach is to find a balance between "information transparency" and "avoiding becoming an attack guide."

This method continues the fundamental principles of "responsible disclosure" and "coordinated vulnerability disclosure" while introducing an additional layer of protection to minimize the risk of premature exploitation of information. Babbush and Neven point out that unverified claims of quantum attacks themselves could undermine market confidence in blockchain technology, leading to new systemic risks.

In specific implementation, zero-knowledge proofs allow third parties to independently verify Google's estimated resources required to break ECDLP-256 without needing access to the specific implementation details of the underlying quantum circuit. The researchers state that by releasing this cryptographic construction, they have completed the conclusion verification without exposing key details.

Google also calls for more research teams to adopt similar mechanisms to promote the establishment of a more responsible vulnerability disclosure system, maintaining necessary tension between information sharing and security protection to reduce the potential impact of future quantum threats on the digital economy.

Blockchain Protection Path: Transitioning to Post-Quantum Cryptography (PQC)

As large-scale quantum computers gradually move from theory to reality, the secure foundation of cryptocurrency and blockchain systems is facing an increasingly clear challenge, prompting the industry to proactively turn to post-quantum cryptography.

This research has significantly reduced the quantum hardware requirements for implementing an attack, thereby advancing the potential risk window in the time dimension. Researchers point out that post-quantum cryptography provides a relatively mature and feasible path for building a blockchain security system resistant to quantum attacks and supporting the long-term stability of digital currencies and the broader digital economy in the quantum era. Since the deployment of relevant solutions takes time, proactive planning and gradual migration will be key to maintaining system trust.

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