Re:Breaking RSA Security with a Low Noise D-Wave 2000Q Quant...
by conformist on Thursday May 07, 2020 @06:35AM
(#23101518)
This.
Essentially, all the quantum annealing stuff that D-Wave does follows the patter of mapping a problem onto a spin glass and then finding the ground state with annealing.
The only really interesting theoretical aspect is finding good maps form hard problems to spin glasses.
This is a nice reference: https://arxiv.org/abs/1302.5843
Re:Breaking RSA Security with a Low Noise D-Wave 2000Q Quant...
by betterunix2 on Thursday May 07, 2020 @08:57AM
(#23102420)
"asymmetric encryption algorithm that is NP-complete"
No such cryptosystems are known, and in fact such a system would also have implications in complexity theory.
Re:Breaking RSA Security with a Low Noise D-Wave 2000Q Quant...
by ohvirginia on Thursday May 07, 2020 @05:26AM
(#23101199)
But circuit sat is not equivalent to solving a multiplication table like this. If you're doing it that way, you're making it way too hard.
To me it looks like they took the factorization problem, which has a lot of well-known (relatively) low-complexity algorithms and imlemented it by mapping it onto circuit-SAT [1] (the multiplication table corresponds to a multiplier circuit which they try to solve in reverse). Circuit-SAT is a proven NP-complete problem. There is currently no known quantum-algorithm that solves NP-complete problems in sub-exponential time.
Note that in the complexity hierarchy NP-complete problems are "harder" than the factoring problem. These are generally bad problems, were not even a quantum-computer helps (and I know of no asymmetric encryption algorithm that is NP-complete when trying to break it, but maybe the quantum-resistant encryption algorithms are better in that regard).
And that's even before we start talking about the limitations of quantum-annealers and the kind of speedups they can gain over classical computers. For a discussion of that, maybe one should start reading Scott Aaronson's blog [2].
[1] https://en.wikipedia.org/wiki/Circuit_satisfiability_problem
[2] https://www.scottaaronson.com/blog/?p=2555