研究组探讨了排除的体积相互作用对线性物理网络局部装配的影响，其中节点是球体，链接是不同长度的刚性圆柱体。为了专注于细长链接的影响，研究组引入了一个最小的3D模型，帮助他们放大这些网络的受限区域，这些网络的遥远部分通过具有非常大宽高比的物理链接的随机沉积顺序连接。该研究表明，这些细长的链接或条状附着在可用体积上而没有相互交叉的非平衡动力学在时间上是对数的，而不是针状填料在较低维度上的代数增长。
研究组将这种性质上不同的行为归因于由问题的3D性质引起的耗竭力激活的延迟。同样重要的是，研究组发现这种慢动力学是亚稳态的，允许他们分析预测由于局部束成核而表征代数生长的动力学尺度。该发现为研究物理网络的局部组装提供了一个理论基准，并对远离平衡的巢状包装的建模产生了影响。
附：英文原文
Title: Logarithmic kinetics and bundling in random packings of elongated 3D physical links
Author: Bonamassa, Ivan, Ráth, Balázs, Pósfai, Márton, Abért, Miklós, Keliger, Dániel, Szegedy, Balázs, Kertész, János, Lovász, László, Barabási, Albert-László
Issue&Volume: 2025-8-4
Abstract: We explore the impact of excluded volume interactions on the local assembly of linear physical networks, where nodes are spheres and links are rigid cylinders with varying length. To focus on the effect of elongated links, we introduce a minimal 3D model that helps us zoom into confined regions of these networks whose distant parts are sequentially connected by the random deposition of physical links with a very large aspect ratio. We show that the nonequilibrium kinetics at which these elongated links, or spaghetti, adhere to the available volume without mutual crossings is logarithmic in time, as opposed to the algebraic growth in lower dimensions for needle-like packings. We attribute this qualitatively different behavior to a delay in the activation of depletion forces caused by the 3D nature of the problem. Equally important, we find that this slow kinetics is metastable, allowing us to analytically predict the kinetic scaling characterizing an algebraic growth due to the nucleation of local bundles. Our findings offer a theoretical benchmark to study the local assembly of physical networks, with implications for the modeling of nest-like packings far from equilibrium.
DOI: 10.1073/pnas.2427145122
Source: https://www.pnas.org/doi/abs/10.1073/pnas.2427145122