Dispersion relation

[Astronuc]

This subject seems to be coming up quite often, especially for those studying wave mechanics.

Here is a brief intro. I'll be looking for better articles and I hope others will contribute references or insight from personal experience.

http://en.wikipedia.org/wiki/Dispersion_relation

and related topics
http://en.wikipedia.org/wiki/Group_velocity
http://en.wikipedia.org/wiki/Phase_velocity

http://tosio.math.toronto.edu/wiki/index.php/Dispersion_relation - note that this is a wiki page from Department of Mathematics at U. Toronto

I also hope to address anharmonic and non-linear systems.

I think it important for students to understand the significance of the higher order spatial (and temporal) derivates with respect to the dependent variable, uxxx or \partial^3_x\phi in the KdV equation.