Quantum Computers are 1M x too small to hack Bitcoin/SHA-256 (opens in new tab)

(newscientist.com)

1 pointseishtmo4y ago3 comments

3 comments

So that's notionally 40 years under Moore's law. There are a lot of unknowns obviously, bit that's still a lot more concerning than the naive calculatikn that says there isn't enough energy in the universe to try enough inputs to find a collision. It will be interesting to see if / how this gets revised down in the future

josephcsible4y ago

Bitcoin relies on the security of ECC too. Doesn't that take way fewer qubits to break?

tromp4y ago

I don't think so, since computing a (double) SHA256 hash is vastly cheaper to compute than multiplying an elliptic curve point with a scalar. So much so, that by default (assumevalid=1), Bitcoin skips verifying signatures up to some recent date in its initial sync.

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3 comments

version_five4y ago

josephcsible4y ago

Bitcoin relies on the security of ECC too. Doesn't that take way fewer qubits to break?

tromp4y ago

j / k navigate · click thread line to collapse