But the Heisenberg uncertainty principle is a fact of nature, and it would be impossible to build a measuring device which could get around it. In 1922 Otto Stern and Walther Gerlach performed an experiment whose results could not be explained by classical physics. Spin is a completely quantum mechanical property of a particle and cannot be explained in any way by classical physics. The word 'spin' is just a convenient way of talking about the intrinsic angular momentum of a particle. Since tumors tend to have a different water concentration from the surrounding tissue, they would stand out in such a picture.
Every quantum particle is characterized by a wave function.
Unfortunately, it is usually impossible to find an exact solution to the equation, so certain assumptions are used in order to obtain an approximate answer for the particular problem. Wave packets, therefore, can provide a useful way to find approximate solutions to problems which otherwise could not be easily solved. First, a wave packet is assumed to initially describe the particle under study. Finding such propagation techniques, and applying them to useful problems, is the topic of my current research. The American Institute of Physics , as a part of a series about the achievements of Albert Einstein.