Since ancient times, man has been trying to know the fundamental principle of the world, what everything consists of. Previously, atoms were considered such a basis. Then it turned out that atoms and even atomic nuclei are divisible. At the turn of the XIX—XX centuries. radical changes have taken place in the natural science picture of the world caused by the latest scientific discoveries in the field of physics and affected its fundamental ideas. As a result of scientific discoveries, the traditional ideas of classical physics about the atomic structure of matter were refuted.