New research shows how a quantum computer could break the encryption of cryptocurrencies. The latest findings are part of a growing concern that current encryption technologies will not be able to withstand increasing computer power. “Bitcoin wallets are protected by the same public/private key pairs vulnerable to all computers,” Denis Mandich, a former US Government IT official and now CTO of Qrypt, a quantum entropy start-up, told Lifewire in an email interview. “Classical computers can guess weak keys while quantum computers can simply calculate them. Once the private key is revealed, all the cryptocurrency associated with that public key can be transferred anywhere and added as a valid transaction to the blockchain.”
Quantum Leap
The new research published in the journal AVS Quantum Science, was undertaken by the quantum computing company Universal Quantum together with academic institutions, demonstrates that a quantum computer with 13 million physical qubits could break Bitcoin encryption within a day, and it would take a 300 million qubit computer to break it within an hour. Scientists also devised a method to reduce the physical size of quantum computers. A cryptocurrency is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank. Coin ownership records are stored in a computerized database using strong cryptography. “Four years ago, we estimated that a trapped ion quantum computer would need a billion physical qubits to break RSA encryption, which is the standard method of encrypting communication today, equating to a size 100m2. With innovations across the board, the size of the computer would now just need to be 2.5m2,” Mark Webber, quantum architect at Universal Quantum and the paper’s lead author, said in a news release. State-of-the-art quantum computers today only have 50-100 qubits, Webber said. “Our estimated requirement of 13-300 million physical qubits suggests Bitcoin should be considered safe from a quantum attack for now, but quantum computing technologies are scaling quickly with regular breakthroughs affecting such estimates and making them a very possible scenario within the next 10 years,” he added.
Keeping Your Virtual Currency Safe
Not everyone agrees that quantum computers will be able to wipe out Bitcoin fortunes. “If blockchain encryption is broken, consequences will be minimal if any as the community will see breaks in the chain.” Terrill Frantz, who leads Quantum Computing programs at Harrisburg University of Science and Technology in PA, told Lifewire in an email interview. “Given what we know today on the capabilities of a quantum computer and the techniques implemented in blockchain, there is no known place to conceive of having an issue here.” Mason Jappa, a crypto mining expert, said In an email interview that Bitcoin is “antifragile” technology. “Meaning, it becomes stronger and thrives as a result of stressors, shocks, and volatility,” he added. “If the threat of quantum computing becomes more immediate and realistic, the cryptographic algorithms in Bitcoin can be changed to quantum-resistant ones. This step will be initiated by both Bitcoin Core developers and Bitcoin users, and there has already been discussion around this topic for many years. It is simply not an immediate threat.” Efforts to develop post-quantum cryptography technology are underway, including an initiative led by the Ethereum Foundation, noted Max Galka, the CEO of Blockchain company Elementus, in an email interview with Lifewire. Honeywell is also working to make blockchain resistant to quantum computing, using physical hardware that supercomputers couldn’t access remotely. “Luckily, we are still a few years off from quantum computers having the ability to break blockchain encryption, which gives developers and engineers even more time to develop solutions,” Galka said. On the other hand, while there are efforts to create quantum-safe cryptocurrency wallets, nothing can be done retroactively to protect the vulnerable ones, some of which were lost by the original miners, Mandich pointed out. “The silent PR release of hackers or nation-states having access to large quantum computers will be the transfer of billions in Bitcoin followed by the collapse of the cryptocurrency ecosystem,” he added.
