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Why haven't quantum computers factored 21 yet?

(algassert.com)
335 points ingve | 1 comments | 31 Aug 25 12:14 UTC | HN request time: 0s | source
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owlbite ◴[31 Aug 25 14:08 UTC] No.45083253[source]▶
So how many gates are we talking to factor some "cryptographically useful" number? Is there some pathway that makes quantum computers useful this century?
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Legend2440 ◴[31 Aug 25 16:09 UTC] No.45084245[source]▶
Realistically, you want millions to billions of qubits to compete with classical computers that already have trillions of transistors.
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1. adgjlsfhk1 ◴[31 Aug 25 20:58 UTC] No.45087021[source]▶
the difference is that you need millions of 1 qbits to factor rsa 4096, but you only need 10s of millions to factor rsa 32k. qbits and quantum time scale almost linearly with factor size, but super-polynomially for regular computers