HOW A REACTIVE SYSTEMS APPROACH MAY LEAD TO FULL DYNAMIC MODELS OF MULTICELLULAR ORGANISMS

One-day experiments on living beings will be, to a large extent, substi-tuted by interactive simulations on computers. A decade ago, computer scientist David Harel, winner of the Israel Prize, the ACM Software System Award, the Emet Prize and four honorary degrees, proposed the scientific grand challenge of modelling a full multicellular organism as a reactive system. He suggested the 1000-cell C. elegans nematode as the model organism. In an estimated 10 to 15 years of intensive work, a multidisciplinary team could construct a full model of this organism, or a similar one, in its development and behaviour. The model would be dynamic, interactive and zoomable, allowing changes and probes on the cellular and molecular levels. Such tools would allow cyber-experiments in order to answer questions too complex for laboratory techniques, including comparisons not only within a species, but also with evolutionarily related species with different forms and behaviours. Thus 21st century research in the life sciences and medicine is poised to undergo a major transition, in which computer science will play a central role, similar to the role of mathematics in the physical sciences of the 20th century.

David Harel

Weizmann Institute of Science

Prof David Harel is a computer scientist at the Weizmann Institute of Science in Israel. He was Department Head from 1989 to 1995, and was Dean of the Faculty of Mathematics and Computer Science between 1998 and 2004. He was also co-founder of I-Logix, Inc., now part of IBM. He received his PhD from MIT in 1978, and has spent time at IBM research, and sabbaticals at Carnegie-Mellon, Cornell, and Edinburgh Universities. In the past he worked mainly in theoretical computer science (logic, computability, automata, database theory), and he now works mainly on software and systems engineering and on modeling biological systems. He is the inventor of Statecharts and co-inventor of Live Sequence Charts (LSCs), and co-designed Statemate, Rhapsody, the Play-Engine and PlayGo. Among his expository books are “Algorithmics: The Spirit of Computing” and “Computers Ltd.: What They Really Can’t Do”, and his awards include the ACM Karlstrom Outstanding Educator Award (1992), the Israel Prize (2004), the ACM Software System Award (2007), the Emet Prize (2010), and four honorary degrees. He is a Fellow of the ACM, the IEEE and the AAAS, and a member of the Academia Europaea and Israel Academy of Sciences.