Granular materials are an important physical realization of active matter. In vibration-fluidized granular matter, both diffusion and self-propulsion derive from the same collisional forcing, unlike many other active systems where there is a clean separation between the origin of single-particle mobility and the coupling to noise. Here we present experimental studies of single-particle motion in a vibrated granular monolayer, along with theoretical analysis that compares grain motion at short and long time scales to the assumptions and predictions, respectively, of the active Brownian particle (ABP) model. Our results show that despite the unique relation between noise and propulsion, a variety of granular particles are correctly described by the ABP model. Additionally, our scheme of analysis for validating the inputs and outputs of the model can be applied to other granular and non-granular active systems.

中文翻译：

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振动自推进颗粒的噪声和扩散

颗粒材料是活性物质的重要物理实现。在振动流化的颗粒物质中，扩散和自推进都来自相同的碰撞力，这与许多其他主动系统不同，在其他主动系统中，单粒子迁移的起源与噪声耦合之间存在清晰的分离。在这里，我们介绍了振动颗粒单层中单颗粒运动的实验研究，以及将短期和长期尺度上的颗粒运动分别与活性布朗粒子（ABP）模型的假设和预测进行比较的理论分析。我们的结果表明，尽管噪声与推进力之间存在独特的关系，但ABP模型可以正确描述各种颗粒。此外，