arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2310.09082cond-mat.stat-mechmath-phmath.MPphysics.data-an
收藏

从访问间隔时间的最大值到饥饿随机游走

From Maximum of Intervisit Times to Starving Random Walks

L. Régnier, M. Dolgushev, O. Bénichou

AI总结:

本文研究随机游走访问间隔时间最大值M_n的统计特性,解决了τ_k相关且非同分布的极值统计难题,其渐近结果可应用于觅食理论并求解d维饥饿随机游走问题,且不同扩散过程在对应普适类下具有共性。

摘要:

近期,学界引入并分析了一个用于量化随机游走探索能力的基础可观测量:当随机游走者已访问k个不同位点时,找到一个从未访问过的新位点所需的时间τ_k。本文研究了τ_0到τ_{n-1}中的最长持续时间M_n的统计特性这一自然问题。该问题属于极值统计这一活跃研究领域,难点在于随机变量τ_k之间既存在相关性,又不服从相同分布。除了这一基础理论层面的意义,本文还证明M_n统计特性的渐近求解在觅食理论中有明确应用,且能解决悬而未决的d维饥饿随机游走问题:该问题中晶格的每个位点初始含有一个食物单元,随机游走者到访时会消耗该食物,游走者在饿死前可在无食物的情况下行走S步。不同类型的过程,包括正常扩散、反常扩散、无序介质中的扩散以及分形中的扩散,在相同的普适类下具有共同的性质。

英文摘要:

Very recently, a fundamental observable has been introduced and analyzed to quantify the exploration of random walks: the time $τ_k$ required for a random walk to find a site that it never visited previously, when the walk has already visited $k$ distinct sites. Here, we tackle the natural issue of the statistics of $M_n$, the longest duration out of $τ_0,\dots,τ_{n-1}$. This problem belongs to the active field of extreme value statistics, with the difficulty that the random variables $τ_k$ are both correlated and non-identically distributed. Beyond this fundamental aspect, we show that the asymptotic determination of the statistics of $M_n$ finds explicit applications in foraging theory and allows us to solve the open $d$-dimensional starving random walk problem, in which each site of a lattice initially contains one food unit, consumed upon visit by the random walker, which can travel $\mathcal{S}$ steps without food before starving. Processes of diverse nature, including regular diffusion, anomalous diffusion, and diffusion in disordered media and fractals, share common properties within the same universality classes.

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。

↑