Quantum Computing Researchers Cut Estimated Cost of Attacking Bitcoin and Ethereum Encryption in Half

source: The Quantum Insider

A team of more than 100 contributors has sharply reduced the estimated computing resources a future quantum machine would need to break the encryption protecting Bitcoin and Ethereum wallets, according to CoinDesk, which obtained the research paper ahead of publication on September 10.

The paper, posted to arXiv and involving contributors from the Ethereum Foundation, Theta Labs, StarkWare and several other organizations, describes a quantum circuit requiring 1,151 logical qubits and roughly 1.3 million Toffoli gates to perform a key arithmetic step used in Shor's algorithm.

Logical qubits represent the machine's working units. Toffoli gates measure the volume of computation it must carry out.

The combined score for those two figures comes to approximately 1.5 billion, more than 50% below the roughly 3 billion benchmark that Google Quantum AI published in March.

The paper notes the comparison is not perfectly direct because the two designs use different accounting methods.

What the Researchers Actually Optimized

The work focused on elliptic-curve point addition for the secp256k1 curve, which underpins the cryptographic system both Bitcoin and Ethereum rely on to keep private keys secure.