# The Wave Packet Theory

• Huijun Yang
Part of the Applied Mathematical Sciences book series (AMS, volume 85)

## Abstract

In this chapter we discuss the basic theory of the wave packet, beginning with a representation of an arbitrary disturbance system in the form of the wave packet. It will be shown that the single wave can be considered a special case of the wave packet. Hence, the wave theory, in general, can be considered the basic ingredient of the wave packet theory. In Section 2.3, the asymptotic behavior of wave is discussed and it is to be consistent with the wave packet representation of the disturbance system. That is, the energy of the disturbance system propagates at the group velocity. The WKB approximation is another way of looking at the disturbance system in the form of the wave packet. This material is addressed in Section 2.4.

## Keywords

Wave Packet Group Velocity Basic Flow Eikonal Equation Single Wave

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## Authors and Affiliations

• Huijun Yang
• 1
1. 1.Geophysical Fluid Dynamics InstituteThe Florida State UniversityTallahasseeUSA