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arXiv 2404.13360cond-mat.stat-mechmath-phmath.MP
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有界与无界空间中的持续与反持续运动:首达问题的求解

Persistent and anti-Persistent Motion in Bounded and Unbounded Space: Resolution of the First-Passage Problem

Daniel Marris, Luca Giuggioli

AI总结:

本文将首达概率的更新理论推广到有界与无界空间中的相关随机游走,提出方向性首达概念,并揭示反射界面处方向反转对强持续运动首达分布多模态性的关键影响。

摘要:

随机运动轨迹中时间相关性的存在是生物、化学和物理系统中普遍存在的现象。持续与反持续运动在许多自然和合成系统中的普遍性,催生了大量关于时间相关运动路径建模的文献。尽管已有大量工作,但在空间有界时,确定各种输运相关量的动力学性质(包括到达一个或多个吸收目标的首达概率或首次命中概率)方面进展甚微。为弥合这一知识空白,我们将首达概率与分裂概率的更新理论推广到相关的离散变量。我们在任意维度的格点上,针对所谓相关随机游走或持续随机游走——即简单格点随机游走在有界与无界空间中的一步非马尔可夫扩展——完成了这一推广。我们聚焦于有界域,并同时考虑超立方格点以及六角格点中的持续与反持续运动。离散形式体系使我们能够将首达的概念扩展为方向性首达,即行走者必须从指定方向到达目标,命中事件才被认定发生。作为对相关运动细胞时空观测的一个应用——这些细胞可能被硬表面排斥或吸引——我们比较了反射域内到达目标的首达统计量,区分反射界面处的相互作用是否引发运动方向反转两种情况。在强持续情形下,我们观察到前者首达分布呈现多模态性,而后者中多模态性被大幅抑制。

英文摘要:

The presence of temporal correlations in random movement trajectories is a widespread phenomenon across biological, chemical and physical systems. The ubiquity of persistent and anti-persistent motion in many natural and synthetic systems has led to a large literature on the modelling of temporally correlated movement paths. Despite the substantial body of work, little progress has been made to determine the dynamical properties of various transport related quantities, including the first-passage or first-hitting probability to one or multiple absorbing targets when space is bounded. To bridge this knowledge gap we generalise the renewal theory of first-passage and splitting probabilities to correlated discrete variables. We do so in arbitrary dimensions on a lattice for the so-called correlated or persistent random walk, the one step non-Markovian extension of the simple lattice random walk in bounded and unbounded space. We focus on bounded domains and consider both persistent and anti-persistent motion in hypercubic lattices as well as the hexagonal lattice. The discrete formalism allows us to extend the notion of the first-passage to that of the directional first-passage, whereby the walker must reach the target from a prescribed direction for a hitting event to occur. As an application to spatio-temporal observations of correlated moving cells that may be either repelled or attracted to hard surfaces, we compare the first-passage statistics to a target within a reflecting domain depending on whether an interaction with the reflective interface invokes a reversal of the movement direction or not. With strong persistence we observe multi-modality in the first-passage distribution in the former case, which instead is greatly suppressed in the latter.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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