- (Quote included. I guess "nonlocality" in involved.)
"How that quantum system 'knows' that it must evolve into an eigenstate can be viewed in (at least) two ways. One is to assume that the quantum system somehow “knows” that an interaction will take place in the future. This is actually less troubling than it sounds, since this kind of so-called nonlocality is part of quantum physics anyway, and does not lead to any observable violations of macroscopic causality.
What is nonlocality? How could a quantum system (like a superposition - is that right?) "know" an interaction will take place?
Source: https://www.quora.com/I-heard-that-...ausing quantum wave-function collapse but me?