ABSTRACT
This chapter addresses wavefields generated by specialized sources of volume forces. These are sources concentrated at a single point of the space. Such right-hand sides of the elastodynamics equations are called point sources (of oscillation), while the point at which they are localized is called the source point. On the one hand, point sources serve as good approximations in cases where outer forces act in a small area. On the other hand, point-source problems allow simple explicit solutions, and arbitrary sources can be conveniently represented in terms of point sources. The chapter considers uniqueness for problems with point sources. The mathematical description of point sources (of oscillation) requires an adequate mathematical tool, which allows dealing with functions localized at a single point. The chapter also considers several types of such point sources, which are important in applications, and outlines the formal aspect of the theory of delta functions.
