Waves are everywhere in our daily life. We all experience sound and light with our ears and eyes, we use microwaves to cook, and radio waves are transmitted from and are received by our cell phones. These are just some examples of waves that carry energy from point A to B. However, we may not know details of the physics underlying all these waves. It is important to understand the mechanisms that generate wave dynamics for a given system. It is not straightforward to explain how an...