The Crushing Blow to Determinism

Up to now, we have summarized quite a number of seemingly bizarre results. However, all of these results can be understood by accepting the idea of wave-particle duality, which may not be predicted from classical physics, but is not intrinsically inconsistent with it. It could be argued that now we simply know more about the nature of matter and light thus the concepts of waves and particles, previously thought to be so different, simply have to be extended to a middle ground. 

You might chalk this disappearance up to a badly designed experiment. There are many other ways to measure the position of an electron (for example, you can scatter light off it). But every experiment ever devised destroys the interference as soon as it becomes possible in principle to distinguish between the slits. You cannot know more 

Low intensity electron beam (only one electron present at a time)  

FIGURE 5.10 If only one electron is present in the system at a time, but there are two possible and indistinguishable paths, the ultimate signal will show interference effects. 

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