A linear chain of hard spheres confined in a transverse harmonic potential is unstable and buckles, if tilted beyond some critical angle. We examine this symmetry breaking using a computational model that was previously applied to buckling under compression. Results are presented in a bifurcation… Read More »Buckling of a tilted line of confined hard spheres
A linear chain of hard spheres, confined by a transverse harmonic potential, buckles under compression between two hard walls. Jacobi functions provide exact analytic solutions of a differential equation (related to the Duffing equation) for the displacement profile of this chain, within a continuum approximation.… Read More »Description of the buckling of a chain of hard spheres in terms of Jacobi functions
Examples of bifurcation diagrams are presented for a chain of hard spheres under compression, which are confined by a transverse potential. The diagrams are modified in the presence of an axial force and show interesting topological rearrangements due to the reconnection of loci of different… Read More »Peierls-Nabarro potential for a confined chain of hard spheres under compression
A new virtual seminar series called GEOMPACK (geompack.com) aims to bring together researchers from a range of disciplines (physics, materials, biology, mathematics, computer science). The series focuses on problems in geometry and packing in materials and biology, and provides an avenue to share new research… Read More »Geompack
We extend a previous analysis of the buckling properties of a linear chain of hard spheres between hard walls under transverse harmonic confinement. Two regimes are distinguished—low compression, for which the entire chain buckles, and higher compression, for which there is localized buckling. With further… Read More »Buckling of a linear chain of hard spheres
Previously we reported on the stable (i.e. minimal enthalpy) structures of soft monodisperse spheres in a long cylindrical channel. Here, we present further simulations, which significantly extend the original phase diagram up to D/d = 2.714 (ratio of cylinder and sphere diameters), where the nature… Read More »Columnar structures of soft spheres: metastability and hysteresis
There is a growing interest in cylindrical structures of hard and soft particles. A promising new method to assemble such structures has recently been introduced by Lee et al. [T. Lee, K. Gizynski, and B. Grzybowski, Advanced Materials 29, 1704274 (2017)], using rapid rotation around… Read More »Theory of rotational columnar structures of soft spheres
Recently a novel type of epithelial cell has been discovered and dubbed the “scutoid”. It is induced by curvature of the bounding surfaces. We show by simulations and experiments that such cells are to be found in a dry foam subjected to this boundary condition.… Read More »Demonstration and interpretation of “scutoid” cells in a quasi-2D soap froth