I've been reading some cursory stuff about quantum mechanics, and I want to understand it better - so I have a little thought experiment that I'm curious about. Let's say there are two rooms that are connected by a thin wall with no window. A person is told to stand in one of the rooms for a short amount of time. In the other room, there's a bucket that's perched very precariously on a high shelf. Based on some particular tiny-particle activity that gets measured by a computer, there's a small chance that the bucket will get prodded and fall off the shelf while the person is standing in the other room. The observer is not told about the bucket or the possibility of hearing a clattering noise. No one else is nearby, and the bucket is automatically reset between tests. If the bucket falls, then the observer hears it, but if the bucket doesn't fall, then the observer is not aware that there was a bucket in the first place. Will the bucket ever stay on the shelf?