In a recent social media post, Blockstream CEO Adam Back has dismissed quantum FUD (fear, uncertainty, doubt) around Bitcoin, exposing that some fearmongering stems from the lack of understanding of how the network actually works.
Writer Josh Otten has argued that a quantum computer could use Shor’s algorithm to break "the encryption guarding Bitcoin’s earliest wallets."
"This would expose the private keys to Satoshi Nakamoto’s fortune, likely crashing the market and destroying trust in the whole system," he predicted.
According to Otten, this is the likeliest scenario that could push the price of Bitcoin to nearly zero in virtually no time.
This implies that the private keys to early Bitcoin addresses could be exposed.
However, Bitcoin wallets rely on elliptic curve cryptography (ECC) for signing transactions, specifically the secp256k1 curve.
Private keys are used to sign transactions while public keys and addresses allow verification. This is not the same as encrypting data. Encryption implies that data is hidden and can be decrypted. Bitcoin's security model is based on signatures that prove ownership without exposing the private key.
Quantum computers threaten the signing algorithm, not encryption per se.
A sufficiently powerful quantum computer could theoretically use Shor’s algorithm to derive private keys from public keys. However, addresses don’t reveal public keys until you spend from them. Early Bitcoin wallets that have never spent their coins haven’t revealed their public keys.
Assessing quantum threat
Ethereum co-founder Vitalik Buterin has warned that the quantum threat is real and measurable.
Solana's Anatoly Yakovenko has estimated that there is a 50/50 chance that enough quantum power could exist to threaten Bitcoin’s cryptography within the next five years.
However, Back has explicitly stated that Bitcoin is unlikely to face a meaningful quantum computing threat for 20–40 years (if ever).
Even the most advanced systems today have high qubit counts but lack the error‑corrected logical qubits needed to run algorithms like Shor’s at scale. Moreover, post-quantum cryptography already exists.
Dan Burgin
Vladislav Sopov
U.Today Editorial Team