11-08-2006, 06:52 PM
Small but important correction. It was well-known that observing a phenomenon changed it (and it's not magical; in order to observe something, you need to add or remove energy from it. If that amount of energy is significant compared to what is being observed, it will change the phenomenon significantly). What Heisenberg did was figured out a way to measure, with great accuracy, the margin of error (essentially, the margin of error). When measuring a very large number of particles simultaneously, it gives very accurate results, which is why it's so important. In other words, he didn't just say that the more accurately you measure the position of a particle, the less accurately you can measure its momentum; he figured out how to calculate HOW MUCH less accurately.