Dec. 6/13, 2002
1:30 pm, ASB 9705

Dr. Gurevich's fundamental work on the theory of Abstract State Machines (ASMs), originally called evolving algebras, is of fundamental importance for theoretical and applied computing science. He formulated the ASM thesis according to which ASMs provide a universal model of computation in a stronger sense than Turing Machines. ASMs step-for-step simulate arbitrary algorithms on their natural levels of abstraction. The ASM thesis applies to sequential, parallel and distributed algorithms. Recently Gurevich was able to prove the version of the thesis for sequential algorithms. After that, Andreas Blass and Yuri Gurevich proved the version of the thesis for parallel algorithms.

The significance of the theoretical concepts developed by Gurevich is confirmed by the substantial impact they have on mathematical modeling of discrete dynamic systems. Indeed, the definition of ASMs have triggered hundreds of research papers in applied computer science. This success is well documented in the annotated ASM bibliography on the ASM web site (www.eecs.umich.edu/gasm/). There is a well-established international ASM community which holds regular conferences and workshops.

Beyond academic research, ASMs have been used in industry as a practical tool for system modeling by leading companies such as Siemens (Munich), and Microsoft (Redmond). Furthermore, ASMs have been adopted as a basis for international standardization of complex modeling and programming languages. For instance, the International Telecommunication Union (former CCITT) has approved the ASM-based model of their specification and design language SDL as the current standard.