system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: In the double slit experiment, how are they so sure that it's the act of observing that introduced a collapse and not some other interference ?
gpt
'Observing' basically breaks down into interaction with the observed particle. After all, if there were no interaction with the particle, then it couldn't be observed - that's why neutrinos are so hard to observe.

Back in the day, people weren't really aware of that, which lead to ideas like Schroedinger's cat being alive and dead at the same time until someone looks inside when interaction already happens at the Geiger counter, at which point the quantum superposition is broken, or Einstein's "Is there a moon when nobody looks?" - Yes, because the particles interact nontheless, and it's not just the act of actual human observation that breaks superpositions.