Adam Back states that Bitcoin faces no substantial quantum threats for at least the next 20 to 40 years. He adds that Bitcoin can adopt NIST-approved post-quantum encryption standards in time.
As a cryptographer cited in Bitcoin’s whitepaper and a cypherpunk pioneer, Adam Back asserts that Bitcoin remains secure from quantum computing threats for the next two to four decades.
On November 15, Back replies to a user on X platform about Bitcoin’s potential risks: “Probably 20-40 years before it’s a problem.” He further explains that NIST-approved post-quantum encryption standards already exist, allowing Bitcoin to upgrade “long before a cryptographically relevant quantum computer exists.”
The discussion stems from a user posting a video of Canadian-American venture capitalist and entrepreneur Chamath Palihapitiya, who predicts that Bitcoin’s quantum threat materializes in two to five years. Palihapitiya notes that quantum computers need about 8,000 qubits to crack Bitcoin’s SHA-256 encryption standard.
During a Cointelegraph interview in mid-April, this cypherpunk suggests that quantum computing pressure might reveal if Bitcoin’s pseudonymous founder remains alive. Back explains that quantum computing could expose Satoshi Nakamoto’s Bitcoin holdings to theft risks, forcing a transfer to new addresses to avoid losing control over the tokens.
Quantum Computing's Current State
Current quantum computers either suffer from excessive noise that prevents encryption cracking or lack the scale needed. For example, Caltech’s neutral atom array—the highest in physical qubits—boasts up to 6,100 physical qubits but still falls short of cracking RSA-2048, which theoretically requires about 4,000 logical qubits.
The reason lies in the fact that 4,000 qubits represent an idealized model assuming perfect local qubits without real-world noise. These qubits qualify as logical qubits.
Error rates
remain lower in ion trap systems like Quantinuum’s Helios, which achieves 98 physical qubits corresponding to 48 error-corrected logical qubits—meaning every two physical qubits yield one usable logical qubit. In universal gate quantum computers, Atom Computing reaches 1,180 qubits, becoming the first system to break the 1,000-qubit barrier in late 2023.
Currently, existing quantum computers stand far from threatening mainstream encryption standards. However, experts debate how long this gap lasts—some predict linear progress, while others expect breakthroughs as the field attracts massive investments.
The "Quantum Threat" We Face Now
Although quantum computers capable of breaking modern encryption seem unlikely in the near term, their potential future existence poses a real threat. “Harvest now, decrypt later” attacks involve adversaries collecting and storing data now, waiting for future technology to decrypt it.
This issue does not affect Bitcoin, as it employs encryption to ensure only legitimate owners access assets. As long as Bitcoin deploys quantum-resistant security measures in time, its safety remains assured.
However, such attacks impact anyone relying on encryption for long-term data security
For instance, dissidents in authoritarian states hope their encrypted data stays protected for 10, 15, 20 years or more.
Smart contract researcher Gianluca Di Bella, specializing in zero-knowledge proofs, tells Cointelegraph recently: “We should migrate to post-quantum encryption standards now.” He notes that practical commercial-level quantum computing might take another 10 or 15 years, but warns that major institutions like Microsoft or Google could deliver solutions within a few years.
This assurance from Back could stabilize investor confidence, potentially boosting cryptocurrency mining profitability as secure networks encourage greater adoption and efficient ASIC miner use.
