Of the four known forces in nature, the electromagnetic force is all pervading, being effective at sub-atomic distances (the realm of the strong and the weak nuclear forces, each being of extremely short range) and at astronomical distances (the realm where the gravitational force is significant). A proper study of electromagnetism is therefore central to physics, being an excellent example of the evolution of a physical theory from basic experiments to a mathematical formulation of great beauty and elegance.

This course reveals the ‘secrets’ of Maxwell’s equations relating time-varying electric and magnetic fields, and the consequential behaviour of plane electromagnetic waves (the reflection and transmission) at interfaces of various pairs of materials. Radiation types will be described (electric and magnetic, dipole and quadrupole) and meaning assigned to complex indices of refraction - the (real) refractive indices and the extinction coefficients. Formulae will be established that describe the properties of radiation from an accelerated charge (examples include synchrotron radiation and cosmic synchrotrons) - the energy loss per cycle, the polarisation of the radiation, and the radiation’s distribution (likened to a searchlight) for charges moving with relativistic velocities.

This course is intended to give the student a physical understanding of the principles of electrodynamics.  In the majority of the lectures, electrodynamics will be described by classical vector field theory.  However, in the last couple of lectures the theory will be described in a moving frame, and generalized using tensor notation (to be consistent with special relativity).  In the laboratory you have the opportunity to experience electrodynamics with the third year lab experiment "Determination of Whispering Gallery Modes in a Uniaxial Cylindrical Sapphire Crystal".  This experiment involves the solution of Maxwell's Equations in a sapphire dielectric cylinder and the surrounding space.  The boundary conditions between the space and sapphire interface, allows the prediction of resonant frequencies, which can be compared with experiment.