A scientific symposium celebrating Professor Alex Hansen’s 70th birthday was held at the Institut Henri Poincaré (IHP), Sorbonne University, Paris, on 19–20 March 2026. Organized by colleagues from PoreLab in Norway, ESPCI in France and UFC in Brazil, the event brought together nearly 40 international experts in statistical physics, porous media, fracture mechanics, and complex systems.
The program highlighted Hansen’s influential scientific legacy, spanning four decades of contributions to the physics of porous and granular media, non‑equilibrium statistical physics, and fracture phenomena. The symposium opened with remarks by Professor Eirik G. Flekkøy, Deputy Director for PoreLab, followed by a keynote lecture from Hansen himself on “Klein’s paradox and its resolution”, reflecting his longstanding engagement with fundamental theoretical problems.
Talks throughout the two‑day program covered topics central to Hansen’s research, including phase‑diagram extrapolation, fracture transport, mixed‑wet percolation, and fluid–solid interactions in complex geometries. Presentations by collaborators and former students illustrated the breadth of his impact and the continuing relevance of his theoretical and computational approaches to contemporary challenges in porous media and complex matter.
The symposium served not only as a tribute to Hansen’s scientific achievements, including his ERC Advanced Grant on multiscale flow in porous media, but also as a gathering of the research community he helped build, reflecting his role as a leading figure in the field and Director of PoreLab.
