Адам Бэк: Квантовая угроза для биткоина не так страшна, как заявляют Translation: Adam Back: The Quantum Threat to Bitcoin Is Not as Scary as Claimed

Quantum systems capable of breaking the cryptography of the first cryptocurrency are not expected to emerge for another 20 to 40 years, according to Blockstream co-founder and cypherpunk Adam Back.

The expert also pointed out that such computers may ultimately never materialize.

The discussion was sparked by venture capitalist Chamath Palihapitiya’s assertion that significant cryptographic computations are just two to five years away. He estimates that approximately 4,000 stable logical qubits will be necessary to crack the SHA-256 algorithm used in Bitcoin.

Back disagreed and highlighted the existence of quantum-resistant algorithms such as the standard SLH-DSA, which is set to be finalized by the National Institute of Standards and Technology (NIST) in 2024.

He believes that Bitcoin, often referred to as digital gold, has enough time to gradually adopt such solutions and «to prepare for the quantum era well ahead of the arrival of practically significant quantum computers.»

Previously, a similar viewpoint was expressed by analyst Willy Woo, who stated that the threat would not become tangible until 2030.

In December 2024, Back commented that advancements in quantum computing would strengthen Bitcoin rather than threaten it. He is among those experts who deem the risk posed by this technology to be exaggerated.

Digital gold is vulnerable to legal attacks from states and corporations, according to renowned cryptographer and smart contract pioneer Nick Szabo.

«To view Bitcoin or any other blockchain as an impenetrable bastion of anarcho-capitalism against government intervention is pure madness,» he wrote.

The expert elaborated that every cryptocurrency has a «legal surface of attack,» which allows governments to influence the network’s operation through miners, node operators, and wallet providers within jurisdictions that uphold the rule of law.

Szabo linked the risks to the increasing volume of arbitrary data in the first cryptocurrency’s blockchain, referring to transactions involving Ordinals, Runes, and BRC-20, which contain images, videos, and other non-financial content.

Debates on this topic arose following the controversial update of Bitcoin Core v30, which raised the data transmission limit in OP_RETURN outputs from 80 to 100,000 bytes. Critics pointed out the potential risks of disseminating illegal content.

It is worth noting that at the end of October, a Bitcoin developer using the pseudonym dathonohm proposed a soft fork that would limit outputs to 83 bytes.