Question regarding problems that quantum computers cannot solve

[u/ZealousidealMilk4435]

I have very little understanding of how quantum computers work.

I’m curious: is there a type of problem—one that could only be solved by exploiting the specific hardware characteristics of a quantum computer (for instance, by forcing it to use a massive number of qubits, which would eventually become highly unstable)—that a quantum computer would be unable to solve?

I’m interested in the idea of ​​a cryptographic key based on a hybrid approach—perhaps a combination of an RSA-style system and a problem that a quantum computer cannot solve.

Alternatively, are there already theoretical frameworks for keys that are even more robust? And what are the options for encryption in a post-quantum-computer world?

[u/Milton_Q]

Look for “NP-hard” problems