Federal Centre for Complexity and Exobiology

About COEX









Katholieke Universiteit Leuven, (K.U.Leuven)

Address: Celestijnenlaan 200D, B-3001 Leuven
Contact persons: Christian Maes, Christian.maes@fys.kuleuven.ac.be; Prof. Chr. WAELKENS, christoffel@ster.kuleuven.ac.be


The Institute of Theoretical Physics at the K.U.Leuven has a long and rich tradition in the study of complex behavior for physical systems. One of the main achievements over the last 40 years was the development of an internationally competitive research group in statistical mechanics and in the theory of dynamical systems.

The Institute of Astronomy of the K.U.Leuven is involved since two decades in the study of the circumstellar media of stars. These studies rely heavily on infrared observations from space, the infrared domain being by excellence the electromagnetic window through which molecular lines and solid-state features of dust particles can be observed.

Research Projects

Theoretical Physics

1 . Study of the emergence of complex behavior from conceptually simple dynamical mechanisms: In a broad sense, statistical mechanics is a transfer mechanics where microscopic laws are connected with mesoscopic or macroscopic behavior. Many aspects of that programme can be transposed to a variety of scientific questions where one needs to understand resulting behavior from underlying details.

The group has been active in unravelling aspects of spatially extended dynamics (probabilistic cellular automata, interacting particle systems) and in finding extensions of the Gibbs formalism in equilibrium statistical mechanics that can cope with physically more unusual models that have however direct relevance to the study of complex systems (self-organized criticality, unusual fluctuation behavior).

2. Nonequilibrium systems: directly related to the life sciences is the study of (possibly small) thermodynamic systems that are kept in a steady state. The statistical mechanics of entropy production and its fluctuation properties is all important here and forms a main research theme. An important field both of inspiration and of application are biological systems which are complex in their composition and structure and where the flow of energy and chemical reactions are never at equilibrium. Life is seen as a steady state in which function, structure, and information are sustained in the presence of energy and chemical flows. Cellular metabolism can be regarded as a spatial and temporal network of chemical reactions and molecular interactions never quite at equilibrium . Current research themes are the statistical mechanics of molecular motors and the theoretical modelling and analysis of single molecule experiments. Biological matter is becoming a common laboratory for us physicists in order to test and extend ideas that transcend the behavior of ordinary matter.

3. Recognition problems and artificial intelligence: the group of neural networks is working on recognition problems and the modelling of intelligent systems. One of the themes is self-control dynamics and optimization of mutual information content. The information content and its ability to act in new environments is function of microscopic structure and dynamics and again, central is the question to describe the properties of that transfer.

SEE ALSO http://itf.fys.kuleuven.ac.be/


Studies with the spectrometers on board the Infrared Space Observatory ISO, launched by ESA in 1995 and operational until 1998, have opened the field of circumstellar mineralogy. In an astrobiological context, this field is of particular relevance for the study of the structure and evolution of the disks which surround young stars, and in which planets are thought to form. A spectacular result obtained by the Leuven group is that crystalline silicates, which before ISO had only prominently been observed in comets, are ubiquitous in the circumstellar disks of young stars: the close match of the ISO spectrum of the star HD100546 with that of comet Hale-Bopp witnesses the fact that the disk of this star is now undergoing the comet-dominated stage which our solar system underwent during its early youth. Another widely publicized ISO result was that also in the disks surrounding evolved binary systems mineralogical processes occur that resemble those of planet formation.

Current research on the circumstellar disks of young stars involve the modelling of the evolution of these disks and the characterization of the numerous different dust species which occur in them. For these studies, the ISO database still is a rich source. New observational developments involve the use of the NASA infrared observatory Spitzer as well as high-angular-resolution observations in the thermal infrared obtained with the Very Large Telescope Interferometer of the European Southern Observatory.

Future projects in this area will also exploit two infrared satellite projects which are now marked as ‘exploration type’ missions, i.e. the ESA cornerstone mission Herschel, the launch of which is foreseen in 2007, and the MIRI-instrument for the NASA-ESA ‘James Web Space Telescope’, to be launched in 2012. C.Waelkens is Co-Principal Investigator of the PACS instrument for Herschel, and as such a member of the Herschel Science Team. He is also Co-PI for the MIRI project and presently one of the four European members of the MIRI Science Team. In terms of financial contribution, PACS and MIRI are the two largest space science instrument projects in Belgium .

Another main science item at the Institute of Astronomy is asteroseismology.

C. Aerts is a Principal Investigator for the COROT mission, and is heavily involved in the Eddington project; both missions are also optimized for the detection of exosolar planets through the transit method.

SEE ALSO http://www.ster.kuleuven.ac.be/index_en.html


Other (Public outreach, conferences, equipments ...)

Institute for Astronomy of the K.U.Leuven Outreach

Design by B-USOC


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