be given as in equation ( . ). Louis de Broglie ( – ) Louis de Broglie, a French physicist, studied history as an undergraduate in the early ’s. His interest turned to science as a result of his assignment to radio communications in World War I.
He received his Dr. Sc. from the University of Paris in . He was professor of theoretical physics at the University of Paris from untill his retirement in .
He was awarded the Nobel Prize in Physics in . ( . ) where ∆ x is the uncertainty in position and ∆ p x (or ∆ v x ) is the uncertainty in momentum (or velocity) of the particle. If the position of the electron is known with high degree of accuracy ( ∆ x is small), then the velocity of the electron will be uncertain [ ∆ (v x ) is large].
On the other hand, if the velocity of the electron is known precisely ( ∆ (v x ) is small), then the position of the electron will be uncertain ( ∆ x will be large). Thus, if we carry out some physical measurements on the electron’s position or velocity, the outcome will always depict a fuzzy or blur picture. The uncertainty principle can be best understood with the help of an example. Suppose you are asked to measure the thickness of a sheet of paper with an unmarked metrestick.
Obviously, the results obtained would be extremely inaccurate and meaningless. In order to obtain any accuracy, you should use an instrument graduated in units smaller than the thickness of a sheet of the paper. Analogously, in order to determine the position of an electron, we must use a meterstick calibrated in units of smaller than the dimensions of electron (keep in mind that an electron is considered as a point charge and is therefore, dimensionless). To observe an electron, we can illuminate it with “light” or electromagnetic radiation.
The “light” used must have a wavelength smaller than the dimensions of an electron. The high momentum photons of such light p h =