In particular we will consider a method of solving these problems and discuss some questions that this research has raised. Very recent astronomical evidence suggests that the Universe is spatially open and will expand forever. In such spacetimes, it proves possible to choose harmonics and define particles unambiguously. This suggests that the structure of the Universe may shape the very foundations of physics, at least as much as the other way around. The deposition of energy in matter by fast electrons is of considerable interest due to the widespread use of electron beams.
Applications range from electron microscopy to the radiotherapeutic treatment of cancer.
It is often the case that the bulk of the energy lost by the incident electrons is due to scattering from the electrons in the target material. I have recently developed a new theoretical approach that treats the quantum exchange between the incident and target electrons in a detailed way. In this talk, I discuss the application of this approach to the study of the stopping of electrons. Questions you were afraid to ask. Come with your repressed questions about the physical world.