标题： 空间捕食者-被捕食者模型中的随机种群振荡 显示英文标题

标题： Stochastic population oscillations in spatial predator-prey models

摘要： 众所周知，在捕食者-猎物相互作用模型中包含空间结构和随机噪声会破坏经典的确定性洛特卡-沃尔泰拉关于中性种群循环的图景。 相反，随机模型会产生寿命较长但最终衰减的不规则种群振荡，这种振荡可以通过密度波动的共振增强机制来理解。 在空间随机捕食者-猎物系统的蒙特卡罗模拟中，可以观察到显著的复杂时空结构。 这些传播的活动前沿会在捕食者和猎物之间产生持续的相关性。 在存在局部粒子密度限制（有限的猎物承载能力）的情况下，捕食者种群存在一个灭绝阈值。 伴随的连续非平衡相变由定向渗透普适类控制。 我们采用基于主方程的Doi-Peliti表示的场论方法，对随机粒子相互作用模型进行（i）将吸收态相变附近的后续作用映射到Reggeon场理论，并（ii）定量地处理物种共存相中种群振荡频率、阻尼和扩散系数的涨落诱导重整化。 显示英文摘要

摘要： It is well-established that including spatial structure and stochastic noise in models for predator-prey interactions invalidates the classical deterministic Lotka-Volterra picture of neutral population cycles. In contrast, stochastic models yield long-lived, but ultimately decaying erratic population oscillations, which can be understood through a resonant amplification mechanism for density fluctuations. In Monte Carlo simulations of spatial stochastic predator-prey systems, one observes striking complex spatio-temporal structures. These spreading activity fronts induce persistent correlations between predators and prey. In the presence of local particle density restrictions (finite prey carrying capacity), there exists an extinction threshold for the predator population. The accompanying continuous non-equilibrium phase transition is governed by the directed-percolation universality class. We employ field-theoretic methods based on the Doi-Peliti representation of the master equation for stochastic particle interaction models to (i) map the ensuing action in the vicinity of the absorbing state phase transition to Reggeon field theory, and (ii) to quantitatively address fluctuation-induced renormalizations of the population oscillation frequency, damping, and diffusion coefficients in the species coexistence phase.