Observed really just means observed. It has no fancy “scientific” meaning.

I think the reason people get stumped on this is because a lot of popsci articles treat the wavefunction as a physical object and thus its collapse as a physical event.

They then get confused as to how simply observing and becoming consciously aware of something can physically alter the system and cause a physical “collapse.”

But Copenhagen (the orthodox interpretation) treats the wavefunction as merely an accounting of your knowledge of how the system was initially prepared and the collapse as just bookkeeping of new knowledge you acquired of its state at a later time.

The collapse is therefore not treated as a physical event at all; you learn something about the system through measuring it and then update your bookkeeping according to the new knowledge (“collapse” it). It’s a formal accounting and not a physical event

If one believes the collapse represents a physical event, this is called a physical collapse theory and you can prove that these must necessarily deviate from the empirical predictions of orthodox quantum mechanics, and so Copenhagen does not uphold the collapse to represent a physical event (in the sense that it represents a physical perturbation to the system) at all but is instead epistemic (dealing witha change to the observer’s subjective knowledge).

They just set up a projector and ran the light through slitted screens. Some light behaved as individual particles and some as waves, while being observed. They didn’t blast it or smash it.

Which is interesting, since everything observable came into existence through pretty violent blasts and smashes.

Edit: now that I think of it, projecting light is blasting it through space, I suppose.

Thanks I saved your post for next downtime I can watch. Unfortunately I ignored chores so that may take a minute. I assume it will need watching as opposed to listening while catching up.