The first video is a neat illustration of the double-split experiment, but it's a little funny to me how our host makes such a mysterious lips-smacking deal over how mere observation causes the particle to change its behavior "as if it were aware of being watched!" This can only be deliberate silliness. The people putting this thing together know full well that at a quantum scale, detection = direct interaction with the particle.It is as if some gigantic quantum physicist wanted to observe me walking down my street, and to do so, threw a bean-bag chair at me at a high rate of speed. As I stagger along recovering from the impact, the physicist, in jubilant wonder, cries: "why, he changed how he was walking - just as if he knew he had been observed...!" Bugger off you prat - you just threw a bean bag chair at me! Of course the electron changes how it acts after the process of being measured. The first time, it passed unmolested through the slit. The second time - from the electron's teensy tiny standpoint, it got mugged. The detector isn't an eye standing to the side. The detector is any device placed directly in the slit that interacts directly with the passing electron and is physically changed by the interaction. The electron is physically changed by the interaction as well.
Or to put a fine point on it: it isn't observation (a conscious process) that changes what is being measured at the quantum level. It is the process of measurement itself. A physical process.We trigger the physical process, so we can use the result it will generate to make an observation. But our tools are so big and clumsy (relative to tiny, quantum-scale phenomenon) that we change what we seek to observe - not by observing it, but by measuring it.
"Bugger off you prat, you just threw a bean bag chair at me" HA! Too funny!! =DAhhh yes, it makes more sense now. (Should have known with all your talents, quantum physics would be one of them - lol). As with most of the videos I post, there are aspects I really like (in this case, the clear visual demonstration of the double slit experiment), and aspects where one eyebrow slowly lifts northward....For example, I've noticed that often people swing a little too far from science (objective/measureable) to mysticism (subjective/based in perception rather than reality) when there really should be a balance. Although the scientists performing the experiments likely follow every scientific protocol, like everything else, the interpretation can be skewed to support almost any point of view. (People believe what they wanna believe. Or as another video points out - "Seeing is not believing, believing is seeing") Although I think they mean/use it in a different context.Anyway, thanks for the comments! :-)
Ah, you're too kind! I'm no quantum guru. I very much struggle to grasp many aspects of quantum theory. But the measurement problem always seemed straightforward enough! I'm strongly leaning toward crediting my sophomore year physical sciences teacher for the fact the concept made some considerable sense going in. That video is very well-done! I loved the visualization. But contrary to what a guy in another of the videos said, quantum physicists do not get "fear in their eyes" talking about the measurement problem. They LOVE to talk about that crap - to explain the differences and implications between the various supposed solutions, and slyly confide which one they're leaning towards...It's a solved problem in physics, but real scientists are tremendously excited by a non-solved problem. Only a non-scientist thinks science needs to be infallible.
"Only a scientist thinks science needs to be infallible"Check out this debate posted on philosophy vs. science. 418 comments!!! Of note is the "Human Ape" or "Ape Human" thread. http://edwardfeser.blogspot.com/2011/02/why-are-some-physicists-so-bad-at.html