Additions and changes have been made to the new edition, taking into account the development of the theory over the past decades. The presentation of the theory of measurements in the quantum field has been significantly expanded and deepened. The form of causality in quantum mechanics is covered in more detail. Expanded description of diffraction scattering and optical model of particles. The concept of the analytical properties of the scattering matrix and the poles of the Regge. Feynman's formulation of quantum mechanics, using integration along trajectories. The simplest problem of nonlinear optics is considered. Many other smaller changes have been made; some archaisms are excluded and the literature has been updated.