Invited Lecture
Constructing an introductory course on diffusion

In most schools of engineering, this is one of the first interdisciplinary courses that third-year undergraduate students are likely to have attended. This presents formidable challenges because any discussion of diffusion phenomena draws heavily on prior knowledge of Physics, Chemistry, and Mathematics. In our traditionally defective way of teaching, these disciplines are presented as self-contained, autonomous units, and it should be the purpose of any instructor of diffusion theory and practice to show how they may be integrated. Heuristic arguments are certainly appealing — thus recommended — but the methods and tools to be developed must be robust enough to not immediately crumble with use. In that connection, attention to a known and consistent notation is vital. For example, Taylor’s theorem should appear as in standard Calculus and not as it might have been displayed in a pre-Newtonian text. Furthermore, one cannot expect these students to be fully familiar with partial differential equations, and yet, that’s the very nature of the diffusion equation. Its properties must be explained. Finally, diffusion in solids suffers from a bewildering variety of “diffusion coefficients." These must be carefully defined and distinguished.

In this lecture, I shall focus on a new course on diffusion that I have designed for another Israeli university and that I am currently teaching. The "boundary conditions" are severe because our semesters consist of only 13 weeks, and it is therefore impossible to cover every aspect of this discipline. I will present my syllabus and explain the reasons for my (sometimes painful) choices.