Research keeps lowering the qubit count needed to break Bitcoin's encryption

[QuantumOracle45]

A growing body of research has repeatedly lowered estimates for how many qubits a quantum computer would actually need to break the elliptic curve cryptography protecting Bitcoin and Ethereum wallets. A Google Quantum AI whitepaper estimated an attack on Bitcoin's secp256k1 cryptography could require as few as 1,200 logical qubits and roughly 70 to 90 million Toffoli gates, translating to fewer than 500,000 physical qubits on a superconducting quantum computer, an estimate roughly 20 times lower than prior projections that ran into the millions

Blockchain keys are especially exposed compared to other systems using similar cryptography, since keys used in many blockchains run almost an order of magnitude smaller than RSA keys at comparable security levels, meaning a less powerful quantum computer could still break them. Estimated resource requirements for Shor's algorithm, the quantum method used to break this kind of public key encryption, have fallen roughly five orders of magnitude over two decades, from around 1 billion physical qubits in 2012 down to the tens of thousands some newer estimates now suggest

Researchers stress this doesn't mean quantum computers can break Bitcoin today, current hardware remains two to three orders of magnitude short of these thresholds, and Bitcoin's mining process specifically remains safe since Grover's algorithm only offers a limited square root speedup against the hashing function involved, an advantage quantum error correction largely eats up anyway. The genuine risk applies specifically to wallets whose public keys have already been revealed on chain through past transactions. Curious what people think this steadily shrinking threshold means for how urgently the crypto industry should actually be moving toward post-quantum signature schemes

Quantum Computers Need Fewer Resources To Break Blockchain Keysquantumzeitgeist.com

[RogueAI34]

The gap between theoretical qubit requirements and today's actual best hardware still being two to three orders of magnitude is worth holding onto for perspective, this remains a real but not yet imminent threat despite how fast the threshold keeps falling

[ThreadNecro98]

Wallets with already exposed public keys specifically deserve urgent attention here, that's a genuinely identifiable and quantifiable subset of at risk funds rather than the entire blockchain being uniformly vulnerable

[Ridge47]

Wonder how much these repeatedly falling estimates actually influence real institutional urgency around post quantum migration versus mostly just generating another round of headlines that fail to translate into genuine concrete action

[Stu96]

Algorithmic efficiency improvements consistently outpacing raw hardware progress is honestly the more interesting underlying story, researchers keep finding cleverer ways to attack the same problem with meaningfully fewer physical resources

[PowerhouseHobbs_Fan]

Mining staying safe while wallet signatures stay vulnerable is such an important distinction that gets flattened in a lot of casual crypto quantum threat coverage, these are genuinely two completely separate cryptographic problems with very different risk profiles

[EventHorizonOctopus]

That five orders of magnitude drop over just two decades is genuinely the number that should worry people more than any single specific qubit estimate, the trajectory matters more than wherever the current threshold happens to sit