Why Use Plane Waves to Solve Maxwell's Equations?

[girlinphysics]

When finding solutions to Maxwells equations we always cosider the case of a plane wave. But are plane waves real/physical solutions we can consider in real life? My guess is not because it is required to propagate infinitely.

So why do we use plane waves to solve Maxwell's equations?

 

[jtbell]

Plane waves are useful approximations for many practical situations. For example, if you are far enough from an oscillating dipole source, and you consider a volume of space that is small enough compared to the distance from the source, the curvature of the waves is small enough that you can ignore it for practical purposes.