Quantum Computers “A Million Times Too Small” to Hack Bitcoin

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  • Quantum computers are currently a million times too small to hack Bitcoin
  • Hacking Bitcoin’s SHA-256 encryption needs 1.9 billion qubits, but currency quantum computers are far behind this
  • It could be a decade before processors get anywhere near this

Bitcoin is safe from quantum computers for quite some time according to the University of Sussex, who say that the first iterations of the machines are still some million times off the requisite size. The threat of quantum computing over Bitcoin has been heavily reported in recent years but is overblown in terms of the capabilities and compatibility of the first such devices, as well as the motives behind using them in such a way, and this latest report appears to have put a lid on such concerns.

Biggest Quantum Computer Still a Million Times Off

The study, conducted by the Ion Quantum Technology Group within the University and reported in the New Scientist, compared the current crop of quantum computers with the computational power needed to hack Bitcoin’s SHA-256 encryption within the 10-minute window afforded by the protocol when a new block is added.

They found that doing so would require a quantum computer with 1.9 billion qubits of processing power, some way off the world’s fastest quantum computer, IBM’s Eagle processor, which was announced in November last year, which operates at 127 qubits. Even if quantum computers were given a whole day to try and hack into Bitcoin instead of just 10 minutes, they would still need 13 million qubits.

Bitcoin Hardly the Prime Target

This means that quantum computers will have to become a million times larger in order to threaten Bitcoin, which the university reports isn’t likely to happen for another decade. And even if they do get to this stage, whether anyone would try and use one to hack Bitcoin as opposed to, say, the military hardware and software of an ideologically opposed government, is doubtful.