论文标题
带有Poissonian开关
Apparent anomalous diffusion and non-Gaussian distributions in a simple mobile-immobile transport model with Poissonian switching
论文作者
论文摘要
我们分析颗粒的移动式iMmobile运输,这些颗粒的移动率和固定阶段之间的切换有限。尽管看似简单的Poissonian切换假设,但我们仍推出了丰富的传输动力学,包括重要的瞬态异常扩散和非高斯位移分布。我们的讨论基于神经元细胞中TAU蛋白的实验参数,但此处获得的结果预计与复杂系统中的一定类过程有关。具体而言,我们得到的是,当平均结合时间明显长于平均移动时间时,在短时和中间时间尺度上观察到瞬时异常扩散,并且对最初的流动性和固定颗粒的分数有很强的依赖性。我们在相关的中间时间尺度上揭示了粒子位移的拉普拉斯分布。对于任何最初的移动粒子,相应的平方平方位移都会显示出平稳的位置。此外,当最初所有颗粒都不动时,我们证明了固定示踪剂的平均平方位移的短时三次立方间依赖性。
We analyse mobile-immobile transport of particles that switch between the mobile and immobile phases with finite rates. Despite this seemingly simple assumption of Poissonian switching we unveil a rich transport dynamics including significant transient anomalous diffusion and non-Gaussian displacement distributions. Our discussion is based on experimental parameters for tau proteins in neuronal cells, but the results obtained here are expected to be of relevance for a broad class of processes in complex systems. Concretely, we obtain that when the mean binding time is significantly longer than the mean mobile time, transient anomalous diffusion is observed at short and intermediate time scales, with a strong dependence on the fraction of initially mobile and immobile particles. We unveil a Laplace distribution of particle displacements at relevant intermediate time scales. For any initial fraction of mobile particles, the respective mean squared displacement displays a plateau. Moreover, we demonstrate a short-time cubic time dependence of the mean squared displacement for immobile tracers when initially all particles are immobile.