ESPCI web site
Séminaire café 2026
| 8 janvier | Présentations des 2ème année - PMMH Gareth Kergourlay & Thibault Papin |
| 15 janvier | Présentations des 2ème année - PMMH Giovanni Russo & Zheming Zhang |
| 22 janvier | Hector Urra - IUSTI Detachment of a highly concentrated suspension drop |
| 29 janvier | José Da Costa et Alexandra Vieira - SU Présentation de SUMMIT, unité de service de Sorbonne Université dédiée à l’ingénierie de la recherche et au développement de collaborations scientifiques et industrielles. |
| 5 février | Léa Cailly - CEMEF, Mines Paris PSL Stretching, contact line receding and breakup dynamics of capillary bridges between a hydrophobic surface and a bath |
| 12 février | Blandine Pommier - CNRS Innovation Comment financer mon innovation ? |
| 19 février | Melissa Dewulf - EnLife, PSL Grand Programme PSL - Engineering Life (short presentation) Matteo Brizioli - Universita’ degli Studi di Milano Surface of biomolecular condensates : a distorted mirror reflecting their material properties Over the past decade, increasing evidence has emerged for the existence and importance of membranelles compartments in cells1. These dynamic structures form via condensation of proteins and RNA, a process known as liquid-liquid phase separation2. Exhibiting fluid-like properties, condensates can rapidly assemble, coalesce and dissolve to regulate diverse biological functions, such as molecular sequestration, gene expression and enzymatic activity3. Their physiological role is inherently related to material properties like viscosity, elasticity and surface tension. Alterations in these properties, through processes like aberrant gelation or aggregation, may be associated with neurodegenerative diseases, where proteins abnormally cluster4. Thus, devising new approaches to reliably characterize condensates material properties is pivotal. In this work, we employ Differential Dynamic Microscopy (DDM)5 to probe in vitro models of biomolecular condensates. This non-invasive technique analyzes microscope images to extract dynamical information akin to light-scattering. By applying DDM to single condensates, we demonstrate its ability to characterize the relaxation dynamics of thermally driven surface fluctuations at the interface between the condensed and the dilute phases, enabling the estimation of key parameters such as surface tension and viscosity. Our approach opens new possibilities for assessing and linking condensate material properties to biological function and dysfunction. References : [1] C.P. Brangwynne, C.R. Eckmann, D.S. Courson, A. Rybarska, C. Hoege, J. Gharakhani, F. Jülicher, and A. A. Hyman. Science, 2009, 324.5935 : 1729-1732. [2] S. Alberti, A. Gladfelter, and T. Mittag. Cell, 2019, 176.3 : 419-434. [3] D. Bracha, M.T. Walls, and C. P. Brangwynne. Nature biotechnology, 2019, 37.12 : 1435-1445. [4] S. Alberti, Simon, and S- Carra. Journal of molecular biology, 2018, 430.23 : 4711-4729. [5] R. Cerbino, V. Trappe. Physical review letters, 2008, 100.18 : 188102. |
| 26 février | Présentations des 2ème année - PMMH Baptiste Vauléon & Petr Soyfer |
| 5 mars | Cecilia Herrero - LPENS How Do Ultrastable Glasses Return to Equilibrium ? Microscopic Insights into Devitrification Glasses are amorphous solids that remain out of equilibrium over long timescales. Their physical properties slowly evolve, and understanding how they relax toward equilibrium is a central problem in condensed matter physics. Ultrastable glasses access deeply supercooled states with very high kinetic stability. When heated, these materials transform back into liquids through a process known as devitrification, yet the microscopic mechanisms governing this transformation are not fully understood. In this seminar, I will present molecular dynamics simulations that probe the spatiotemporal evolution of deeply supercooled liquids after a rapid temperature increase. We find that relaxation does not occur uniformly throughout the system, but proceeds through spatially heterogeneous dynamics with clear similarities to crystal melting. The transformation unfolds in distinct stages, generates large dynamic length scales, and deviates from standard kinetic descriptions. Our results are in good agreement with experimental observations of ultrastable glass melting and, beyond reproducing the phenomenology, provide a physical understanding of the mechanisms controlling the transformation. |
| 12 mars | Julia Dal Pont - ESPCI Présentation et échange autour de Schéma directeur DD&RSE (Développement durable et responsabilité sociétale et environnementale), par Annie COLIN, Régis ROSMADE et Julia DAL PONT Depuis 2021, l’ESPCI s’engage et prend des mesures pour renforcer sa gouvernance en matière de transition écologique. C’est dans ce cadre-là que l’ESPCI a souhaité structurer sa démarche et créer une feuille de route qui permettra de fixer des objectifs qu’elle souhaiterait atteindre d’ici 2030 : le schéma directeur DD&RSE. L’objectif pour l’établissement est de s’inscrire comme un acteur de la transformation sociétale et ainsi mettre son expertise dans ses trois piliers, que sont la recherche, l’innovation et l’enseignement, au service de la société et des changements qui l’accompagne. Ce plan d’action a pour but d’impulser une dynamique globale, sans contraindre, ni restreindre les libertés de la recherche et de l’enseignement. Il répond également à une obligation réglementaire, puisque l’État impose à tous les établissements de l’ESR d’en réaliser un. L’objectif de cette présentation et d’ouvrir une discussion sur le contenu du schéma directeur afin d’intégrer des remarques et commentaires, pour rendre la stratégie la plus proche possible des attentes et contraintes des chercheurs, tout en fixant un cap pour rendre l’école plus responsable. |
| 19 mars | Pas de réunion café (PC Focus) |
| 26 mars | Pas de réunion café (RNL) |
| 2 avril | Pierre-Antoine Maes - PMMH |
| 9 avril | Marie-Luce Nadal - PMMH |
| 16 avril | Nicolas Laubato-Dauzier |
| 23 avril | Simeon Djambov |
| 30 avril | Eléonore Duval |
| 7 mai | Nicolas Harmand - Laboratoire Jean Perrin |
| 14 mai | Ascension |
| 21 mai | Julien Le Dreff - LadHyX |
| 28 mai | Reda Belbahri - Owkin |
| 4 juin | Eva Kanso |
| 11 juin | PC l’été ☼ |
| 18 juin | Alice Pelosse - PMMH |
| 25 juin | Onaïa Savary - Météo France Toulouse |
| 3 septembre | Giulia Merlini - MAP5 (ENPC) Waveguide model for shear wave elastography of the cornea This work addresses the mathematical modelling of elastic wave propagation within the cornea. The underlying application is the detection through shear wave elastographic measurements of pathologies associated to changes in the biomechanical properties of the cornea, such as glaucoma and keratoconus. Supported by experimental evidence of guided wave propagation in ex-vivo cornea, we model the tissue as an incompressible homogeneous elastic plate with finite thickness. Under plane strain and harmonic plane wave assumptions, the problem becomes one-dimensional over the finite thickness of the plate. We derive a well-posed variational formulation for incompressible guided waves. Computing dispersion curves and modal profiles leads to a non-linear eigenvalue problem, whose mass and stiffness matrices can be computed explicitly with Legendre polynomials. A key feature of this framework is that fluid-structure interaction at the posterior surface can be easily incorporated, modelling the fluid as acoustic and purely incompressible, with transmission conditions at the boundary. Numerical results show that the presence of the fluid strongly affects the modal profiles through the thickness and decreases the propagation speed of the first modes, especially at high-frequency. Finally, anisotropy is introduced to account for the layered collagen microstructure of the cornea. Results are consistent with numerical simulations of a 3D anisotropic model of the cornea entailed with a complex description of collagen structure, providing physical interpretation and insights of simulations. |
| 10 septembre | Eugene Rhee - Institut Charles Sadron (Université de Strasbourg) Translating Complexity through Art, Design, and Interaction Scientific public outreach allows disparate groups to collaborate and connect, advancing equity and accessibility in scientific research and knowledge. Through my U.S. Fulbright project, in collaboration with my affiliates, Mrs. Wiebke Drenckhan at the Institut Charles Sadron and Mr. Sébastien Soubiran at the Jardin des Sciences at the University of Strasbourg, I seek to understand how researchers, educators, and young students can collaborate strategically to share science with wider audiences and connect as communities. As a designer and engineer whose work has ranged from fluid dynamics research to co-designed projects with local communities, I am excited by the opportunity to work in Strasbourg to explore how art and design can translate complex scientific research into engaging and educational experiences for young students. In this talk, I will share my interdisciplinary journey across science, engineering, design, and public engagement. From the SurferBot project—a little robot that combines fluid dynamics research with science-art outreach for children—to my Fulbright project, I explore how art, design, and playful interaction can make complex science more accessible, engaging, and meaningful. Ultimately, I ask how we might move beyond simply explaining complexity and instead create experiences that invite people to explore, question, and connect with it. |
| 17 septembre | Philippe Agard - ISTeP (SU) ’’L’aZUR’’ — la Zone Urbaine de la Rivière un projet multi-facettes et original = une embarcation/péniche amarrée au pied des campus PMC et MNHN ...et du PMMH Un projet unique au monde, à forte valeur ajoutée (ASU, ESR, Ville de Paris,...) 1. un croisement inédit et foisonnant d’expertises de laboratoires de pointe, levier d’une recherche décloisonnée et innovante (capteurs/brevets/applis), à l’intersection des disciplines 2. un miroir tendu à nos modes de vie, à nos santés et à l’impact du changement climatique sur une ressource critique (l’eau) et ses usages 3. un lieu iconique au coeur de Paris pour l’accueil d’experts et ≠ publics, un levier pour la science participative et l’éducation (y compris la formation continue) |
| 24 septembre | Emanuel Bertrand - ESPCI Paris, UMR SPHERE, Université Paris-Cité Controverses autour de la thermodynamique de non-équilibre L’ouvrage de 1979, La Nouvelle Alliance, du physicien théoricien Ilya Prigogine et de la philosophe Isabelle Stengers, est à la fois un livre d’histoire et de philosophie de la physique et un essai philosophique sur la place de l’homme dans la nature. Il a suscité (et suscite encore parfois) de vives controverses interdisciplinaires à propos de la thermodynamique de non-équilibre. |
| 1er octobre | Mario Marcel - Ecole Estienne & PMMH Projet fig. 1 - LABO : Illustrer la recherche pour des écoliers |
| 8 octobre | Intelligence Artificielle au PMMH - discussion |
| 15 octobre | Esteban Valdecasa (LadHyX) - reporté |
| 22 octobre | Lara Koehler - Max Planck Institute for the Physics of Complex Systems Passive memory reshapes active persistence Many active systems move in complex environments whose mechanical response is slow and history dependent. To address this regime, we study the collective dynamics of self-sustained active particles in non-Markovian media within a generalized Langevin framework with memory. We focus on the competition between the timescales of active persistence and viscoelastic relaxation in the environment. Using a minimal interacting model with an exponential memory kernel, we show that environmental memory qualitatively reshapes motility-induced phase separation of self-propelled active particles. When the memory timescale is comparable to the active persistence time, delayed response generates an effective anti-persistence that suppresses clustering and produces a broad metastable regime with slow nucleation dynamics. By contrast, for long memory timescales, reduced friction at short times enhances the effective propulsion velocity and restores phase separation. Our results demonstrate that the surrounding medium can actively regulate the emergence, stability, and dynamics of collective organization in active matter. |
