An animation of the Gyroid phase in (computational) assemblies of pear-shaped colloidal particles. Click here for the animation. This is an animation produced by Philipp Schönhöfer, as part of his postgraduate research
A video of tomographic data of a real experimental wet sphere pack. Read more
Animation file: (Nature Comms Suppl Info page) Read more
Congratulations to Thomas Pigeon on completing a lovely animation of the 8-srs structure, the 8-fold highly symmetric intergrowth of 8 equal-handed gyroid graphs. Thomas came to Murdoch University for a project in 2017, and self-taught himself the mastery of houdini. Thomas, thanks for sharing your beautiful animation: Read more
Here’s Myfanwy Evans‘ animation of her Surface Evolver study of diffusive coarsening. Diffusive coarsening is the process by which the cells of a random liquid foam grow or shrink as a consequence of slow gas diffusion through the cell membranes, driven by pressure differences between adjacent cells. Read more
An old animation of mine, showing a bunch of falling spheres that fall into a jar. I’ve been meaning to put online for a while – here it is! Read more
The cubic Gyroid surface is a “bicontinuous” minimal surface that divides space into two intertwined network- or labyrinth-like subdomains. Read more
The evolution of the spatial structure of foams, during mechanical shear but also during diffusive coarsening, occurs by continuous geometric deformations maintaining cell topology interspersed with sudden topological transitions when cells change neighborhood. Following a topological transition, the foam undergoes significant and large-scale geometric deformations. This animation shows an animation of the Surface Evolver simulations of sheared foams, used as the basis of the analysis in Evans et al, PRL 111, 138301 (2013).
Animation with Plateau borders: (mp4)
Animation without Plateau borders: (mov)
We have used these simulation techniques to study the stress propagation in foams, as published in Evans et al: Quasistatic simple shearing flow of random monodisperse soap froth is investigated by analyzing surface evolver simulations of spatially periodic foams. Elastic-plastic behavior is caused by irreversible topological rearrangements (T1s) that occur when Plateau’s laws are violated; the first T1 determines the elastic limit and frequent T1 avalanches sustain the yield-stress plateau at large strains. The stress and 
shape anisotropy of individual cells is quantified by Q, a scalar derived from an interface tensor that gauges the cell’s contribution to the global stress. During each T1 avalanche, the connected set of cells with decreasing Q, called the stress release domain, is networklike and nonlocal. Geometrically, the networklike nature of the stress release domains is corroborated through morphological analysis using the Euler characteristic. The stress release domain is distinctly different from the set of cells that change topology during a T1 avalanche. Our results highlight the connection between the unique rheological behavior of foams and the complex large-scale cooperative rearrangements of foam cells that accompany distinctly local topological transitions. (this is the abstract of Evans et al)
Publications:
Evans et al, Networklike Propagation of Cell-Level Stress in Sheared Random Foams , Phys Rev Lett 111, 138301 (2013)
Authorship:
This animation was produced by Myfanwy Evans, from Surface Evolver data produced in cooperation with Andrew Kraynik.
Investigating how tightly objects pack space is a long-standing problem, with relevance for many disciplines from discrete mathematics to the theory of glasses. Here we report on the fundamental yet so far overlooked geometric property that disordered mono-disperse spherical bead packs have significant local structural anisotropy manifest in the shape of the free space associated with each bead.
The three cubic triply-periodic minimal Diamond, Gyroid and Primitive surfaces are related to each other by the so-called Bonnet transformation. That means they are specific members of a single one-parameter family of surfaces, called the Bonnet family with free parameter t for the specific values t=0 (Diamond), t~38o (Gyroid) and t=90o (Primitive). However, in contrast to the D, G and P surfaces, all other members of that family have self-intersections. The animation shows the transformation of a single asymetric patch in E3 (top left), of an extended patch where the coloring of the asymmetric patch has been retained and also showing the three-fold rotation axis common to all members (bottom left) and of a large enough patch of the surface that illustrates the self-intersections (bottom right). In that last image one side of the surface is orange, and the other green. Also shown are the tiles of the complex plane that (via the Weierstrass equation) give rise to the asymmetric unit patch.
Animation file: (40MB MPG)