|MadSci Network: Physics|
Dear Nuno, You are clearly refering to the wave-particle duality of matter/energy. As Einstein told us, E=mc^2, which fundamentally tells us that matter and energy are interchangeable - in other words that energy is matter and matter is energy. So particles, which are matter, can also act like waves, which is energy. The problem is that if you send an electron beam or a photon beam (light) through two holes, the result is an interference pattern. This is clearly wave behaviour. However, if you measure to see when an electron (or photon) passes through the holes, then the behaviour at the other end is not wave- like, but rather particle-like. This is really bizarre behaviour and is a fundamental issue dealt with in Quantum Mechanics, a branch of physics that deals with the smallest units (quanta) of energy/matter, such as the particles we all know and love, like electrons, protons, photons, neutrinos, quarks, etc. In very simplistic terms, Quantum Mechanics tells us that there is an uncertainty associated with particles (like electrons) and that uncertainty leads them to behave in their energy form - like a wave. If you remove the uncertainty, then they behave like particles. When they behave like particles, they can only go through one hole or the other, BUT when they behave like waves, they can go through both holes and create the interference pattern. (Please note: this is a very simplistic discussion of a very complex physics topic.) The discussions about the wave-particle duality of matter and energy is very fascinating, but would require a lot more space than I am entitled to here. Let me suggest that you go to the following url, which is a search on google for [wave particle duality] http:// www.google.com/search?q=wave+particle+duality This search will bring up whole bunch of sites that talk about this issue and should cover the topic much better than I can in this short space. Good luck with your studies, Todd Jamison Chief Scientist, Observera, Inc.
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