ABSTRACT

Chapter 5

Green's Functions

for the Helmholtz Equation

In the previous chapters, we sought solutions to the heat and wave

equations via Green's function. In this chapter, we turn to the reduced

wave equation

r

u+ u = f(r): (5:0:1)

Equation (5.0.1), generally known as Helmholtz's equation, includes the

special case of Poisson's equation when = 0. Poisson's equation has a

special place in the theory of Green's functions because George Green

invented his technique for its solution.