SUURI-COOL Seminar

Modeling form growth in curved spaces using Riemannian L-systems

July 17 (Thu) 16:00 - 17:30, 2025

Christophe Godin (Research Derector, Inria, Univ Lyon, France)

In the past 50 years, the formalism of L-systems has been successfully used and developed to model the growth of filamentous and branching biological forms. These simulations take place in classical 2-D or 3-D Euclidean spaces. However, various biological forms actually grow in curved, non-Euclidean, spaces. This is for example the case of vein networks growing within curved leaf blades, of unicellular filaments, such as pollen tubes, growing on curved surfaces to fertilize distant ovules, of teeth patterns growing on folded epithelia of animals, of diffusion of chemical or mechanical signals at the surface of plant or animal tissues, etc. In this talk, I will describe how we extended the formalism of L-systems to model the growth of branching structures in curved spaces. We will discuss how the space may feedback on the growing form and contribute to shape. I will also look at examples, where the space in which the form is growing is not necessarily a surface embedded in the euclidean 3-dimensional space, but is rather a space intrinsically curved, i.e. curved but not embedded in any higher-dimensional space. The possibility to use these more abstract Riemannian spaces potentially opens new avenues for formalizing rules driving the morphogenesis of living forms.

Venue: via Zoom / SUURI-COOL (Kyushu)

Event Official Language: English

Topological Photonics and the four-dimensional quantum Hall effect

July 3 (Tue) 15:00 - 17:00, 2018

Tomoki Ozawa (Senior Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))

In this seminar, I will give an introduction to topological photonics, that is, the study of topological band structures and resulting topological phenomena in photonic systems. I will first review basic concepts of topological band structures, and then explain what it means to realize topological band structures in photonic systems. I will particularly emphasize some important differences with respect to solid-state electron systems. I then present some of my own works in topological photonics, such as the synthetic dimensions in photonic systems, which allows one to explore models and phenomena in high dimensions including the four-dimensional quantum Hall effect.

Venue: 1F Meeting Room, AIMR Main Building

Event Official Language: English

Including an ocean mixing model in atmospheric data assimilation: a case of Typhoon Soudelor 2015

April 17 (Tue) 15:00 - 15:30, 2018

Kohei Takatama (Postdoctoral Researcher, Data Assimilation Research Team, RIKEN Center for Computational Science (R-CCS))

Venue: Maskawa Hall, 1F, Maskawa Building for Education and Research

Event Official Language: English

Compact-star phenomena and equation of state

December 28 (Thu) 10:30 - 11:30, 2017

Shun Furusawa (Special Postdoctoral Researcher, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))

Venue: SUURI-COOL (Kyoto)

Event Official Language: English

Theoretical study on the universality in biological clock and its species-specificity

December 27 (Wed) 16:00 - 17:00, 2017

Gen Kurosawa (Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) / Research Scientist, Theoretical Biology Laboratory, RIKEN)

Venue: SUURI-COOL (Kyoto)

Event Official Language: English

Mathematical Modeling of Retinal Cellular Mosaic Pattern Formation

December 27 (Wed) 13:30 - 14:30, 2017

Noriaki Ogawa (Postdoctoral Researcher, Interdisciplinary Theoretical Science Research Group (iTHES), RIKEN)

Venue: SUURI-COOL (Kyoto)

Event Official Language: English

Topology of linear operators and topological insulators

December 27 (Wed) 10:30 - 11:30, 2017

Yosuke Kubota (Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))

Venue: SUURI-COOL (Kyoto)

Event Official Language: English