The research groups within the biological, soft and complex systems research area study the physics of a broad range of biological and soft materials. This spans both experimental and theoretical research.

We study the physics of a broad range of biological and soft materials

Promotor: J.N. Kok, Co-Promotor: A.J. Knobbe

Complex systems can be characterized as systems in which multiple components interact with each other, often in non-linear ways. The main goal of this research will be to investigate if and how the international tax system can be defined and modelled as a complex system. Approaching the international…

Addressing the core novel objective of scalably assessing the impact of possible interventions through counterfactual prediction based on spatio-temporal data.

DSE 2.0 concerns research on DSE techniques for complex dCPS

In this thesis, we extend the concept of null models as canonical ensembles of multi-graphs with given constraints and present new metrics able to characterize real-world layered systems based on their correlation patterns.

How can complexity science advance intelligence transformation?

The financial system needs complexity theory to predict economic crises like the 2008 meltdown. An international team of scientists, including Leiden physicist Diego Garlaschelli, state this in a paper published in Science on February 19th.

The authors of the article expect automation to improve accuracy in less complex programmes but worsens with increased complexity

For many system in statistical physics the microcanonical and canonical ensemble are equivalent in the thermodynamic limit, but not for all.

For the first time, astronomers have detected the presence of complex organic molecules, the building blocks of life, in a protoplanetary disc surrounding a young star. The discovery reaffirms that the conditions that spawned the Earth and Sun are not unique in the Universe. The results are published…

In this thesis, we show that we can use Shimura’s CM theory to explicitly compute the Hilbert class field of any primitive quartic CM field.

The thesis addresses the long-term dynamical evolution of hierarchical multiple systems.

What are the functions of the endocannabinoid system?

Protein–protein complexes are formed via transient states called encounter complexes that greatly influence the formation of the stereospecific complex.

This thesis seeks to combine two different research topics; Multi-Objective Optimization and Complex Network Analysis.

Systems with local constraints is a new finding in recent researches on complex systems. The heterogeneous spatial interactions and the temporal dependencies among those numerous units make it difficult to describe by traditional statistical physics.

Promotor: Peter Stevenhagen

Promotor: E. Bouwman, Co-promotor: S. Bonnet

Stars like the sun are born in large molecular clouds existing from gas and dust. During the formation process, the chemical composition of the material can be altered drastically by the changing physical conditions.

In photoactivated chemotherapy (PACT), a biologically active compound is caged by a light-cleavable protecting group.

Essays in Archaeology and Assyriology Dedicated to Diederik J.W. Meijer in Honour of his 65th Birthday

This thesis is comprised of three chapters covering the theme of studying semistable varieties by looking at their dual combinatorial objects.

The Leiden Complex Networks Network (LCN2) aims at bringing together scientists from different disciplines, based on a common interest in both theoretical models and empirical analyses of networks and graphs.

I am working with colloids coated in a lipid bilayer and functionalized with DNA to create interesting flexible microstructures that move due to Brownian motion. We analyze their motion and calculate their soft and stiff modes to get a better understanding of microscale spring networks.

Serge Lemay is professor of Iontronics at the Huygens-Kamerlingh Onnes laboratory, Leiden Institute of Physics. He came to Leiden University in early 2026, where he intends to concentrate on the physics of mixed electronic-ionic charge transport. These processes are at the heart of many of the technologies…

Lipsius, Cleveringaplaats 1, 2311 BD, Leiden

This thesis describes the genetic and prokaryotic diversity of giant barrel sponges.

Light-Harvesting Complex II (LHCII) is responsible for light absorption and excitation energy transfer in plants and photosynthetic algae, while in high light it undergoes conformational changes by which it quenches excitations to prevent photodamage.

The Computer Systems, Imagery & media (CSI) research programme performs research on methods and techniques for the design, implementation and application of advanced computer systems, in particular parallel, distributed and embedded computer systems.

Researchers at LIACS are working to devise the computers of tomorrow that will be the backbone of the Cloud and Edge computing paradigms as well as the Internet of Things. In this respect, we are involved in research and development of high performance computing systems, embedded & real-time computing…

Issues such as climate change, the depletion of natural resources or social inequality are too complex to be addressed from a single scientific discipline or by a single country. Leiden University has the expertise to bring the resolution of these enormous problems a small step closer.

The Collective Experience of Empathic Data Systems (CEEDs) consortium developed novel integrated technologies that support experiencing, analysing and understanding of very large datasets.