Bitcoin might be at risk from a new quantum math trick that breaks digital ownership

A new algorithmic advance lowers the qubit count needed to break ECDSA, the signature scheme securing roughly 6.9 million BTC including Satoshi-era P2PK addresses. Lead with the concrete number — not 'quantum threat someday', but a measurable shrink in the resource gap between current quantum hardware and the cryptography under Bitcoin. The angle: explain ECDSA vs hash-based addresses (P2PKH protects via SHA-256 until you spend; P2PK does not), why old Satoshi coins are uniquely exposed, and what a soft-fork to post-quantum signatures would cost the network. Reader is technically literate — give them the math, not the FUD.