Dr Orsola Rath Spivack
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' (I've found it!), but 'That's funny...'" -Isaac Asimov


Most years I teach a PartIII course on Direct and Inverse Scattering of Waves. Lecture notes and various resources are available on Moodle to students on the course. Here are some slides that give an overview of the course.

Some interesting phenomena about waves, related to this course, are illustrated below.

The movies below show the intensity fluctuations resulting from the propagation of a Gaussian beam in an extended random medium (which can be described by the scintillation index):

Changing the source position Changing the angle of incidence Changing the source intensity

Refocusing for time-reversed waves in a random medium is an effect that was first observed experimentally, and that can be used for the inverse problem of reconstructing a source field. The figures below show an initial Gaussian beam forward propagated then time-reversed, displaying refocusing.

There is usually at least one PartIII essay available associated with the course, although the exact topic changes year on year. If you're interested in doing one of the essays, or would like to propose your own, please get in touch with me and I'll be happy to discuss it.