论文标题
正交跑步行走
Orthogonal run-and-tumble walks
论文作者
论文摘要
考虑到正交运动方向的平面跑步行走。在方向状态之间使用通用过渡概率提出问题之后，我们关注对称情况，从而提供概率分布函数（在拉普拉斯 - 风格域中），均方根位移和过渡速率参数方面的有效扩散常数。作为案例研究，我们处理并讨论两类运动，替代/正向和各向同性/向后，并在可能的情况下获得概率分布函数在时空域中的分析表达。最后，我们还讨论了循环运动的情况。相对于标准2D活动运动，在循环和向后（正向）情况下观察到（增强的）有效扩散率。
Planar run-and-tumble walks with orthogonal directions of motion are considered. After formulating the problem with generic transition probabilities among the orientational states, we focus on the symmetric case, giving general expressions of the probability distribution function (in the Laplace-Fourier domain), the mean square displacement and the effective diffusion constant in terms of transition rate parameters. As case studies we treat and discuss two classes of motion, alternate/forward and isotropic/backward, obtaining, when possible, analytic expressions of probability distribution functions in the space-time domain. We discuss at the end also the case of cyclic motion. Reduced (enhanced) effective diffusivity, with respect to the standard 2D active motion, is observed in the cyclic and backward (forward) cases.
