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In 1985 Egon Börger published his influential monograph on computation theory, logic, and complexity (

Now, only 35 years later, the rapid progress in computing has led to a fascinating variety of interconnected systems that are used to support, manage, and control almost all aspects of our life. There is hardly an area that has not yet been penetrated by computing, and still there are many open challenges for the continuation of this success story. We are now dealing with systems of systems that are characterized by the following properties: 1) they operate in

For instance, if we consider advanced manufacturing, all equipment will integrate electronic and mechanical parts with continuous behaviour, software with discrete behaviours, and sensors and actuators for their integration. Each piece of equipment constitutes an autonomous system of its own, and all the equipment of a shopfloor form a system of systems. This can be taken further to systems integrating all systems within a city. Any collection of systems that collaborate to achieve a common task can be considered a system of systems.

The key challenge for

• Is there a theory of computation that faithfully covers all the aspects of systems of systems that occur in practice?

• Is there a methodology grounded in such a theory of computation that permits the definition and classification of complex systems and the provision of means for specification, systematic development, validation, and verification?

• Is there a methodology that permits reasoning about problems and their solutions in terms of correctness and complexity?

A first answer was given in 1985 by Gurevich’s “new thesis” (

While these developments provided evidence that ASMs can take over the role of the formal languages in computation theory, it took until 2000 to develop the sequential ASM thesis (

The behavioural theories yield variants of ASMs that can be used for rigorous systems development. Furthermore, logics for the reasoning about deterministic, non-deterministic and reflective ASMs followed (

In summary, what is needed is an enhanced theory of computation on structures comprising behavioural theories, logic, and complexity. The theory must provide the backbone for the systems of systems we deal with in practice in the sense that it reflects precisely on arbitrary levels of abstraction how systems in practice operate. Furthermore, the theory must guide the development of methods for systems engineering in practice as well as methods for the analysis of system behaviour.

Therefore, based on the challenges that I described briefly above my ambition for the development of theoretical computer science is driven by the vision of a complete scientific penetration of computing in practice, and the journal section should contribute to this. That is, I aim to obtain as much as possible an understanding of the challenges arising in practice. So, the goal is to have journal contributions that are grounded in the scientific abstraction process transferring practical problems into abstract problems for theoretical computer science. Then I aim to obtain solutions of these abstract problems including classification by expressiveness, complexity, feasibility, etc., so the journal section should contribute decent advanced computer science theory. Finally, I aim to see how the theoretical developments feed back into practice in the form of concrete languages and methodologies that can provably solve the problems that inspired the development of the theories.

The important first step, recruiting a board of Associate Editors sharing the overall vision, has been made. The next steps, launching special research topics on behavioural theory, logic, and complexity theory, will follow.

The author confirms being the sole contributor of this work and has approved it for publication.

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.