The recent hot topic in the cryptocurrency community is the potential threat that quantum computing poses to the encryption algorithm of Bitcoin. Adam Back, the founder and CEO of Blockstream, recently shared his views on this issue.
On September 9th, Google announced the development of its new generation chip, Willow, which successfully overcame the key challenge of quantum computing. The chip is capable of performing computations with 105 qubits, which can solve problems that traditional computers would take a billion years to solve in just 5 minutes.
The birth of Willow has sparked a debate among the cryptocurrency community, with concerns about whether Bitcoin’s encryption algorithm will be vulnerable to quantum computing in the near future. Well-known venture capitalist Chamath Palihapitiya recently claimed that about 8,000 Willow chips would be enough to crack Bitcoin’s SHA-256 algorithm.
However, Adam Back, a legendary figure in the Bitcoin world and the founder and CEO of Blockstream, immediately refuted this claim. He emphasized that it is not possible to increase the number of qubits by connecting a large number of chips with 105 qubits. He stated that in this decade, and even possibly in the next decade, it is far from achievable for humans to have a computer with one million qubits.
Adam Back further discussed the threat of quantum computing. In response to a tweet on September 21st, he stated that it may not be necessary to take such action. Bitcoin can become quantum ready by using a Taproot leaf that commits to a future soft-forkable Post-Quantum (PQ) signature opcode and a hash-based key scheme. This will allow for a smooth transition to a PQ-ready Schnorr signature, while still paying the current signature sizes. This approach would help to calm people’s fears.
According to Cryptonews, Adam Back’s point is that quantum computing might actually enhance the security of Bitcoin. It will drive developers to build a network that is resistant to quantum attacks by using upgrades like Taproot and implementing post-quantum cryptography techniques to prepare Bitcoin for future quantum threats.
Adam Back believes that Bitcoin can use the Taproot upgrade to create code that can withstand quantum computing attacks. By ensuring that this code has “forkability,” it can be periodically updated to address any vulnerabilities exposed by quantum computing, without the need for a complete overhaul of the Bitcoin blockchain.
Next, Bitcoin can transition to the updated Schnorr signatures, which are more efficient and secure digital signatures for the blockchain. This will further enhance the defensive capabilities of the Bitcoin protocol.
Adam Back emphasizes that the threat of quantum computing will not become a reality for at least several decades. Additionally, anti-quantum signature technologies will continue to develop more compact and mature solutions in the future. Bitcoin users can safely migrate their funds through existing Schnorr signatures or future anti-quantum signature schemes without increasing current transaction costs.
He stresses that this mechanism will help the Bitcoin community prepare in advance while maintaining efficiency on the blockchain.