BeauHD posted from the harvest-now-decrypt-later dept.
[Mark Webber at the University of Sussex, UK, and his colleagues] calculated that breaking bitcoin's encryption in this 10 minute window would require a quantum computer with 1.9 billion qubits, while cracking it in an hour would require a machine with 317 million qubits. Even allowing for a whole day, this figure only drops to 13 million qubits. This is reassuring news for bitcoin owners because current machines have only a tiny fraction of this -- IBM's record-breaking superconducting quantum computer has only 127 qubits, so devices would need to become a million times larger to threaten the cryptocurrency, something Webber says is unlikely to happen for a decade.
The study has been published in the journal AVS Quantum Science.
