Benjamin: Quantum codebreaking requires millions of physical qubits due to error correction
Simon Benjamin · Simon Benjamin on Architectures for Quantum Computing · Y Combinator · May 25, 2018 · at 48:11
Oxford quantum theorist Simon Benjamin explains why implementing cryptographic algorithms like Shor's algorithm requires millions of physical qubits rather than just thousands.
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“Breaking codes is in the category of things that needs at least thousands of qubits. But because it's a big, tough, long-running task, it also needs this whole error correction thing to be going on. And that boosts the size of it, because once you say, oh, wait, I need error correction, then you have to do this thing we talked about, where each logical qubit is actually a bunch of physical qubits. And for a really long argument, it might need to be a lot of them. So you'll be from thousands into millions of qubits to do the code breaking stuff.”
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