arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0907.1775physics.soc-phcond-mat.stat-mech
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非线性Q投票模型

The non-linear q-voter model

C. Castellano, M. A. Munoz, R. Pastor-Satorras

摘要:

我们引入了一个非线性的变体的选民模型,q-选民模型,其中q邻居(可能重复)的选民咨询改变意见。如果q个邻居同意,投票者接受他们的意见;如果他们没有一致的意见,投票者仍然可以以概率$ε$翻转其状态。我们在一个完全连接的网络上(即在平均场中)求解模型,并计算退出概率以及达成共识的平均时间。我们分析了最近提出的朗之万方程的角度,旨在描述两个($Z_2$对称)吸收状态的系统中的通用相变的结果。我们发现,在平均场中,q-选民模型对于高$ε$表现出无序相位,而对于低$ε$表现出有序相位,从一个到另一个有三种可能的方式:(一)独特(广义选民样)过渡,(ii)一系列的两个连续的伊辛样和定向渗滤过渡,和(iii)一系列的两个过渡,包括最终状态取决于初始条件的中间状态。这第三个(迄今未探索)的情况下,出现了一种新的类型的有序动力学,是合理的,并发现是特定的平均场,即波动明确显示洗出来的空间扩展系统。

英文摘要:

We introduce a non-linear variant of the voter model, the q-voter model, in which q neighbors (with possible repetition) are consulted for a voter to change opinion. If the q neighbors agree, the voter takes their opinion; if they do not have an unanimous opinion, still a voter can flip its state with probability $ε$. We solve the model on a fully connected network (i.e. in mean-field) and compute the exit probability as well as the average time to reach consensus. We analyze the results in the perspective of a recently proposed Langevin equation aimed at describing generic phase transitions in systems with two ($Z_2$ symmetric) absorbing states. We find that in mean-field the q-voter model exhibits a disordered phase for high $ε$ and an ordered one for low $ε$ with three possible ways to go from one to the other: (i) a unique (generalized voter-like) transition, (ii) a series of two consecutive Ising-like and directed percolation transition, and (iii) a series of two transitions, including an intermediate regime in which the final state depends on initial conditions. This third (so far unexplored) scenario, in which a new type of ordering dynamics emerges, is rationalized and found to be specific of mean-field, i.e. fluctuations are explicitly shown to wash it out in spatially extended systems.

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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