Let's say we put tracking detector (eg. a cloud chamber or a more advanced device) behind the double slits.
What would we see?
I think the interference pattern is three dimensional. So there are hyperbolic regions where waves cancel. So in these regions we wouldn't see particles. But speaking of a tracking detector, which direction the streaks would point to then?
Searching in the topic on the other hand I found a different view that says that the detector would reveal via the trajectory which slit the particle come from, so no interference pattern at all. But this way how would particles know in advance what kind of device I want to measure them?