There is no algorithm that can guarantee an answer to a question within a finite amount of time.
Computing Theories
Computing Theory Usage
Which Computational Universe Do We Live In? | Quanta Magazine
Many computer scientists focus on overcoming hard computational problems. But there's one area of computer science in which hardness is an asset: cryptography, where you want hard obstacles between your adversaries and your secrets. Unfortunately, we don't know whether secure cryptography truly exists. Over millennia, people have created ciphers that seemed unbreakable right until they were broken.
https://www.quantamagazine.org/which-computational-universe-do-we-live-in-20220418


Seonglae Cho