Axe 4 : Models, data, calculation and system complexity

This Data, Models, Calculations and Complex Systems axis concerns fundamental research questions with a strong focus on the development of applications for various real systems in the exact, experimental, human or social sciences. The interdisciplinary dimension of this axis is based on a back and forth between theory and applications: fundamental research feeds the world of applications and vice versa, applied research brings fundamental problems to be solved.

Modeling plays a key role in this area and encourages the convergence of mathematics and computer science with various other disciplines: physics, biology, ecology, economics, sociology and linguistics. These mathematical, numerical or symbolic approaches enable an increasingly detailed representation of reality, for example using non-linear mathematical equations or numerical simulations that are ever more sophisticated thanks to the processing power of high-performance computing. These approaches have difficulty in understanding complex systems characterized by the interdependence of several processes leading to the emergence of collective behaviors. Chaos, adaptation, self-organization or spontaneous order appear, for example, in the evolution of the climate, ecosystems, living organisms, software infrastructures and communication systems, and social and economic organizations.

Data has established itself as a means of enriching these models, calculations and representations of these complex systems. With the development of data models and observation and fusion methodologies adapted to large masses of heterogeneous and multi-source data, knowledge extraction is an emerging field of research that will be studied in relation to artificial intelligence techniques.

The complexity of the problems faced also favors the emergence of systemic approaches. The evaluation of the potential impact of human activities on the environments concerned is now unavoidable in the exploration of new methodological paths for the construction of models. Taking into account the interactions of the real system with its environment plays an important role and represents challenges in terms of decision-making and actions with economic spin-offs or in terms of risk and resource management.


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