International Conference on Percolation and Disordered Systems - Theory and Applications - organized by Armin Bunde (Giessen) and Shlomo Havlin (Ramat-Gan) Schloß Rauischholzhausen, Justus-Liebig-Universität Giessen, Germany July 14 - 17, 1998

This volume Percolation and Disordered Systems contains 72 invited and contributed papers presented at the International Conference on Percolation and Disordered Systems - Theory and Applications - held between 14 July and 17 July 1998 in Schloss Rauischholzhausen at Giessen University. About 100 scientists from 15 countries attended the conference, testifying to the great interest in this active field of research. The conference provided a forum in which a wide range of scientific disciplines was discussed, ranging from biology, chemistry and physics to material sciences and geosciences, and hopefully will act as an important stimulus for new progress in the interdisciplinary field of percolation and disordered systems. The papers presented at the meeting and published in these Proceedings are divided into five topical areas:

1. Percolation: Theory
2. Percolation: Applications
3. Disordered Systems
4. Liquids and Glasses
5. Localization

We wish to thank all who presented talks and posters for their efforts to make their presentations of the highest quality. We also wish to thank the members of the International Advisory Committee, A Blumen, J.F. Gouyet, H.J. Herrman, Y. Klafter, S. Miyazima, H.E. Roman, H.E. Stanley and D. Stauffer, for valuable suggestions and for their help in refereeing the submitted manuscripts that appear in this volume. We are very grateful to Jan Kantelhardt, Jose Luis Gruver, Anke Ordemann, Markus Porto, and Nehemia Schwartz for their help and advice during all phases of the conference.

We feel special gratitude to one of the editors of Physica A, H. Eugene Stanley, publishers Jan Visser and Luuk Holla and desk editor Rolf van der Sanden for their great help during all stages of the preparation of these Proceedings.

The conference, which is documented in these Proceedings, has been made possible by financial support from the Deutsche Forschungsgemeinschaft. This is highly appreciated, as is the encouragement and additional support received form the Minerva Center of Mesoscopics, Fractals and Disordered Systems.

We devote these Proceedings to the memory of our dear friend Shlomo Alexander who died in a tragic traffic accident few days after this meeting. We all enjoyed his talk on Can one understand glasses and all of us benefited from his stimulating comments and ideas on both lectures and posters. During the whole conference, Shlomo was very relaxed and inspired by the unique atmosphere in the beautiful castle of Rauischholzhausen. We remember him dancing with Esther in the lobby of the castle in an improvisated evening party.
Shlomo was one of the fathers of the fields covered by the conference and full of ideas for the future. He passed away much too early and we will all remember him! We appreciate that Pierre-Giles de Gennes wrote a personal note in his memory for these Proceedings.

Armin Bunde and Shlomo Havlin
November 1998

Shlomo Alexander died in a traffic accident on August 6, 1998. He was a leader of our generation.

I met him first at the Weizmann Institute, in the sixties: a thin, tall, absent minded boy, with an experimental education on nuclear resonance, (coming from S. Meiboom), and a theoretical practice from a visit to Phil Anderson. But he already had his own style: thinking deep, arguing a lot, and, if necessary, computing with utmost elegance. We became close friends. I admired the whole family. Shlomo's father, E. Alexander, had been a founder of the Hebrew University, on mount Scopus. Many famous physical chemists (which Shlomo and I learned to know much later) had been the students of E. Alexander. At the time, Shlomo's wife Esther was busy with three young children. She had been a partisan, at the age of 15 in Budapest; later she had escaped from the iron curtain, to meet this young student (and political activist) which was Shlomo in the fifties...

They moved to Jerusalem in 1969 -and Shlomo set up his theory group on condensed matter- We all remember his work on Helium, atoms adsorbed on graphite and the resulting incommensurable transitions. In 1976, he visited us in Paris: we talked to him about polymers, but soon the roles were reversed: he analysed deeply the structure of grafted polymer layers (brushes) and pointed out certain scaling features which none of us had seen. Much later, he made a basic (and poorly recognised) contribution to the theory of rubbers: showing why a realistic rubber, with all interactions included, should display a very special type of scalar elasticity. This was, in fact, the starting point of=20 his reflection on the mechanical behavior of random systems.

We were, at that time, very excited about percolation clusters. I came to Israel, as often, with an open question: what happens if the clusters are superfluid? I had looked at a few trivial cases such as loops, etc. Shlomo entered into this with strength; he discussed all the magnetic properties of the clusters below threshold. He also clarified the case of regular fractals, e.g. superfluid Sierpinski gaskets, etc.

By that time the children had grown up, Esther had returned to the University, and had become a well known economist in Israel. Shlomo watched this with admiration, and collaborated efficiently with her, helping to set up quantitative formulations of Esther's revolutionary ideas. For many years, they shared their time between Israel and California. In Los Angeles, Shlomo produced some major science: on fractons, on electrolytes, on quasi crystals... More generally, during these years, he became the mental guide of many of us- I still remember his advice on certain avalanche problems in granular systems.

We had a special session in Les Houches a few years ago, to celebrate him -and her. We have a videotape of his own talk, which was full of thoughts, and of emotion. We shall not forget him.

P. G. de Gennes