Blockchain Developers Are Racing to Protect Against the Quantum Threat. Here's What It Means for Bitcoin and Ethereum Investors.
Google says breaking Bitcoin's signatures needs fewer than 500,000 qubits. The best machines running today have about 2,500.
Overview
Think about the lock on your front door. Now imagine a locksmith who can glance at the outside of that lock and work out the exact shape of your key. There's no picking, forcing, or breaking anything. The locksmith just looks at the security tool you show to the whole world every day, then walks right in.
That is roughly what a big enough quantum computer would do to Bitcoin (CRYPTO: BTC) and Ethereum (CRYPTO: ETH). Every time you spend from a crypto address, you publish a public key. Today, using that public key to derive the matching private key would take a normal computer longer than the universe has been around.
Details
A powerful quantum machine running Shor's algorithm turns that into an afternoon. Google Quantum AI, a division of Alphabet, put numbers on it in March: about 1,200 to 1,450 logical qubits, meaning the reliable kind you get by welding hundreds of today's error-prone physical qubits into one. With superconducting hardware, that works out to fewer than 500,000 physical qubits and a runtime of 18 to 23 minutes. Researchers from the Ethereum Foundation and Stanford co-signed the paper.
Source
Originally published at www.fool.com.