- Is there any NP-Problem that can't be (maybe even proven) solved by quantum computers. I'm not talking about quantum NP-Problems (if that's even a thing), but about normal NP.
- If that NP Problem exists could you also use it for cryptography, since I don't want to buy a quantum computer just to be secure.
EDIT: I'm not talking about NP-complete, because that would have no use (I think) in cryptography and also not about symmetric key encryption.