New Study: Breaking a Bitcoin Key May Need Just 29,588 Qubits

A French startup called Alice & Bob has published research suggesting that a powerful future quantum computer (a next-generation computer that uses the strange rules of physics to solve certain math problems far faster than normal machines) could break a Bitcoin key in about 62 minutes.

To understand why this matters, here's the basics. Bitcoin wallets are protected by two keys: a public key (like your bank account number, which can be shared) and a private key (like your secret PIN, which controls your money). Normally, it's impossible to figure out the private key from the public one. But a strong enough quantum computer could, in theory, do exactly that — and then steal the coins.

The new study estimates it would take:

• 29,588 physical qubits (the basic building blocks of a quantum computer)
• About 62 minutes of computing time

This is roughly 17 times fewer qubits than Google researchers estimated in March (they suggested under 500,000). However, the studies used different hardware designs, so the numbers aren't directly comparable.

Which Bitcoins are most at risk? Since cracking a key takes much longer than the 10 minutes between Bitcoin transactions, attacking a fresh transaction is hard. The real danger is coins whose public keys are already visible on the blockchain — for example, old wallets or reused addresses.

According to Glassnode co-founder Rafael Schulze-Kraft:

• 6.26 million BTC (about 31.2% of all Bitcoin) sit at addresses with exposed public keys
• 4.33 million BTC are vulnerable due to address reuse

The takeaway: The researchers urge the crypto world to start moving toward post-quantum cryptography (new security methods designed to resist quantum computers) as soon as possible. Importantly, quantum computers this powerful don't exist yet — this is a warning about the future, not an immediate threat.

This is an AI-generated summary. Read the original article at: https://forklog.com/news/issledovanie-dlya-vzloma-klyucha-bitkoina-mozhet-hvatit-29-588-kubitov-i-62-minut