Persistent Complex Systems
The scientific study of complex systems has a broad and long tradition. Research spans across physics, mathematics, AI, computer science, biology, cognitive and neuroscience, the social sciences and economy, where one analyses complex systems such as biological cells, brains, social networks, the internet, industrial plants, power grids, transportation systems, social and political networks, or pandemic spreading. The Bernoulli Institute assembles an outstandingly rich collection of researchers whose work is connected to the study of complex systems. We focus on two main questions:
Qualitative change and development. A particularly important, yet largely open question is to understand how complex systems adapt and extend (or degrade) their very structure and functionality over time. Examples are the development of a human from a fertilized cell to an educated adult, or of our planet’s climate system, or - on a seemingly much simpler level - the wear and tear and possible repair of a household appliance. Qualitative change arises from interactions between micro- and macroscale levels of organization in a complex system. Understanding and predicting qualitative change mandates the integration of modeling methods that are traditionally restricted to different levels of granularity, like describing a neuron in a brain with the help of electrochemical differential equations, while at the same time using logic formalisms to capture the rational reasoning processes carried out in the same brain.
Robustness. A likewise crucial and open question associated with complex systems is what makes them resilient against external damage, internal faults, unpredictability of the environment, aging, and other disruptive effects. Complex systems must have capabilities to stabilize themselves, learn, repair themselves, and find alternative adaptive input-output strategies for their continued viability. Both questions are connected: a system can adapt to strong disruptions only through qualitative change. Understanding persistent complex systems - that is, systems which can stay viable for a long lifetime - is a challenge that has dramatically acquired societal relevance.