Lecture -- Dispersion Relation & Index Ellipsoids 

Thanks a lot for the simple and clear explanations !!! Please keep going!!!

Fab! I wonder can you in principle have a complex k in one direction and real in another since the dispersion relations are quadratic. In which case can one wave be evanescent and the other propagating.

Thank you so much!

Amazing thank u so much

This is great -- thank you!

Amazing lecture