Topic 2

Complex Systems: from non-equilibrium processes to biological matter

Statistical physics of equilibriumd systems provides a strong framework to classical thermodynamics. However, most of the condensed matter systems encountered in biological, industrial or natural systems develop out of equilibrium because of the influence of external forces or because they cannot return to equilibrium (glasses). Those systems are often non-linear, disordered or complex; interactions between their elementary components can lead to the emergence of new properties. The objects of researches come from diverse fields such as glasses, granular materials, soft matter, simple and complex fluids, active or biological matter, lasers. Themes studied are varied too: fracture, interface, materials in suspension, instabilities, transitions, turbulence, mix, transport, networks, and information. However the approaches used are the same, specifically in statistical physics. 

Understanding the slow and emerging dynamics in out of equilibrium systems thus represents one of the greatest current challenges in physics. Those systems are omnipresent, from the nano-scale to the astronomic scale.

(i)They can’t simply be understood by adapting the tools of equilibrium physics. New concepts must be developed to understand them.
(ii) They are directly connected to important societal needs concerning energy, climate, natural risks or health.

Paris-Saclay campus brings together many teams at the best international standards who work on these fields. Through this priority theme, we would like to encourage these teams to interact and to establish one common conceptual framework. Transdisciplinary projects comporting theoretical, numerical and experimental aspects will enable the structuring of the scientific community thanks to lines of research matching the fields of physics in which scientific breakthroughs are expected for the years to come.

  • disordered and glassy systems
  • soft matter and biological systems
  • active matter and living systems
  • fluids and lasers: instabilities, chaos and turbulence
  • theoretical interdisciplinary applications

The theme has open, for the second phase of PALM, to physics and interfaces, specially in biology :

  • membranes, behavior bacteria, viruses, DNA and protein physics, mechanics, cell and tissue morphogenesis, biological fluids, active transportation and in the living 

Deformation_dun_gel_colloidal_durant_le_sechageDeformation of a colloidal gel during drying (200 μm scale)

Transition_laminaire_2Laminar turbulent transition in a shear flow : stationary patern emerging local turbulence.

Image_dejection_dADN_dun_virus_bacterienDNA expulsion image from bacterian virus (cryoEM).

Plateforme_GYROFLOW    Micro_endommagement_observe_sur_la_surface_de_rupture_du_verre_plymerique   Capture_decran_2013-07-05_a_09.22.02
 GYROFLOW plateform : turbulence in rapidly rotating systems.    

Micro-damage (parabolic mark) observed on the fracture surface of a polymer glass.

  Convection thermique dans un fluide avec une viscosité dépendant de la température.


Liste of projects funded by topic 2 of PALM

Contact : Gianguido BALDINOZZI (SPMS)