Partial Differential Equations in Physics: Lectures on Theoretical Physics, Volume VI is a series of lectures in Munich on theoretical aspects of partial differential equations in physics. This book contains six chapters and begins with a presentation of the Fourier series and integrals based on the method of least squares. Chapter II deals with the different types of differential equations and boundary value problems, as well as the Green’s theorem and Green’s function. Chapter III addresses the classic problem of heat conduction and the intuitive method of reflected images for regions with plane boundaries. Chapters IV and V examine the Bessel functions, spherical harmonics, and the general method of eigenfunctions. Chapter VI highlights the problems in radio waves propagation, always considering the earth as a plane. This book is of great benefit to mathematicians, physicists, and physics teachers and undergraduate students.