Table of contents

The author discusses Heisenberg's approach to quantum theory and the associated Hamiltonian.

A short undergraduate course on the use of microprocessors in electronics is described. Students are prepared for the eventual use of microprocessors in practical situations.

A Hele-Shaw cell can be used to explore a variety of phenomena that involve surface tension and viscosity simultaneously. Being essentially two-dimensional the effects are easy to observe, and often simple to calculate apart from fine details. Waves growing exponentially on an unstable interface, and tear drops falling slowly down the cell, are interesting examples.

The authors describe a ripple tank used to study the short wave optics of extended undulating refracting boundaries. Several examples of caustics and diffraction observed with the apparatus are presented and compared with predictions of catastrophe optics, in which they are in complete agreement. The authors discuss the implications of this work for the conventional uses of ripple tanks to demonstrate wave phenomena, with particular emphasis on possible errors in inferring the forms of the water surface from the patterns of light observed.

An apparatus is described which can be used by students to study electric birefringence (the Kerr electro-optical effect). Using pulsed electric fields, the birefringence is observed as a transient phenomenon which is also instructive in an understanding of rate processes. Experiments are outlined which enable dipolar properties and size characteristics of molecules and particles to be determined.

The resonant behaviour of a nonlinear LC circuit and two inductively coupled nonlinear LC circuits is examined experimentally. The amplitude and the phase response curves for primary and secondary resonances are shown.

The consideration of the interaction of two point charges in different frames of reference can be used as the starting point of the unified presentation of electromagnetism, if the students are familiar with the basic ideas of special relativity. Therefore, in an introductory lecture, the fundamental idea of physics, namely the unification of forces which at first are considered as different, can be exemplarily demonstrated.

The properties of plane electromagnetic waves in free space, and evanescent waves which can exist near planar boundaries are discussed in detail, and their physical characteristics compared. The discussion is then generalised to other configurations, and with the help of Fourier synthesis several problems are considered from a unified physical viewpoint. Topics covered include particle accelerators, antennas, diffraction gratings, the radiation from curved surface guides, from atoms, from electrons moving in curved paths and Cherenkov radiation.

The authors show for a simple problem where analytical calculations can be performed, the time evolution of the wavefunction describes the motion in phase space, first through the time evolution of a density pulse and secondly by considering the Wigner distribution function. In the classical limit this last distribution exhibits a very complex physically meaningless structure but by smoothing with a double gaussian kernel, the correct limit is obtained.

It is pointed out that the Minkowski space analogue of the well known theorem about the intersection of the heights of a triangle has a not too far-fetched physical interpretation.

The results of an analysis on the development, over a period of about 20 years, of the theoretical studies on relevant chapter of solid-state physics are summarized and discussed. From the data collected, of which some samples are presented, it is possible to draw some inferences of a sociological nature on the dynamics of development of modern scientific research and its interplay with its own social background.