|MadSci Network: Physics|
Dear Jerónimo, To the best of our knowledge, the electron is the best example of a point particle. It has no radius. In other words, it cannot be divided into anything smaller. The slit experiment is evidence of the wave behaviour of the electron, and of all matter-- all matter can behave as either a wave or as a particle. A good textbook on modern physics should give a good explanation of this. The other effects you describe are due to the interaction of the electric field of the electron with the electric field of the matter through which it is passing. I should point out that string theory proposes that everything is made up of 'strings', including electrons. However, this is *only* a theory. We do not have the ability to test this theory.
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