Jaan proposed a wonderful topic for my fourth year project - ``Percolation'', which was then a very new idea, just beginning to ``percolate'' through the Physics Community. Jaan told me there was this new idea and he wanted to learn about it and so I should do a project on it. I just took a copy of that project down from my shelf, where I keep it next to copies of the projects and theses my own students have carried out, and realised that it has multiplied many times over.
Percolation has become a lifelong research passion of mine as well as a very exciting field involving hundreds of physicists and mathematicians during the last 25 years. It is not the only topic where Jaan has been ahead of the fashions that seem to grip the physics community. He encouraged us by example to use computers wisely as a tool in research long before ``Computational Physics'' became so popular, and worked himself on quantum magnets before they, in turn, became fashionable in the era of high temperature superconductivity.
Since my graduation from UNSW in 1980, I have been based at the Technion in Haifa, having fun with Computational Physics, including Percolation and Critical Phenomena and more recently Atomistic Simulations. We are especially interested in visualization for simulations of atomistic and spin systems and I show here two figures from a manuscript for a column that will soon appear in ``Computers in Science and Engineering''. The picture on the left is of an aluminium drop on a sapphire substrate and on the right a split-interstitial defect in diamond is shown.
I have tried to pass on to my 15 current and recently graduated students some of the computational and statistical mechanical principles that Jaan taught me. The computers are better, ``Mathematica'' rescues those of us who cannot do algebra as well as Jaan can, but the basic concepts remain the same. I thank Jaan for the thorough grounding I received in all aspects of Physics Research.