Louis+de+Broglie


 * Louis de Broglie **

In the early 1920s a young French prince by the name of Louis de Broglie was working on his PhD. De Broglie submitted his thesis in 1924 in which he made a daring proposal. If light which we find easier to consider as a wave, can, according to Planck and Einstein, sometimes behave as a stream of particles, then it would be a rather nice and symmetric feature of nature if moving particles could sometimes behave like waves.

Think of it this way. Through the equation e=mc2, we know that matter can be considered somewhat like frozen energy and the two can be transformed into each other. So, since light, or rather EM radiation, which is just a form of energy, can have a split personality, then why could matter not have one?

De Broglie suggested that every material object could be associated with a matter wave, which a wavelength that depended on its mass. The more massive a particle, the shorter the wavelength of its associated wave. The de Broglie wavelength of a cow would be trillions of times smaller than atomic dimensions and far too tiny to ever be detected, while an electron travelling at a few metres a second has a de Broglie wavelength equivalent to the width of a human hair. This is large enough for its wave nature to show up in experiments, therefore the manifestation of the interference pattern in the double-slit experiment.

This means that anything in motion including us, have a wavelength; we are waves as well.