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arXiv 2603.04844cond-mat.stat-mechcond-mat.dis-nn
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接触过程中的扩散紊乱

Diffusion disorder in the contact process

Institute of Physics, Academia Sinica(中央研究院物理研究所);Department of Physics, Missouri University of Science and Technology(密苏里科技大学物理系);Physics Division, National Center for Theoretical Sciences(国家理论科学中心物理学部)

Valentin Anfray, Manisha Dhayal, Hong-Yan Shih, Thomas Vojta

AI总结:

研究发现接触过程中的扩散紊乱破坏了定向渗透临界点,使其属于无限随机性 universality 类,并通过有效模型解释了扩散紊乱对治愈速率的影响。

摘要:

我们研究了空间非均匀扩散对接触过程非平衡相变的影响。在接触过程中,定向渗透临界点已知对加入空间均匀扩散项具有稳定性。相应地,我们发现扩散速率中的淬火随机性通过接触过程场论的功率计数法被证明是无关的。然而,大规模蒙特卡罗模拟显示,这种扩散紊乱会破坏干净的定向渗透临界点。相反,该转变属于与具有感染或治愈速率中随机性的接触过程相同的无限随机性 universality 类。为了解释这些结果,我们开发了一个具有无限扩散率的有效模型;它表明扩散紊乱会在治愈速率中产生有效的随机性。同样的机制也出现在场论描述中:尽管扩散紊乱通过功率计数法无关,但它在重整化下产生标准随机质量紊乱。我们讨论了该机制对其他吸收态转变和非平衡相变的一般有效性。

英文摘要:

We study the effects of spatially inhomogeneous diffusion on the non-equilibrium phase transition in the contact process. The directed-percolation critical point in the contact process is known to be stable against the addition of a spatially uniform diffusion term. Correspondingly, we find quenched randomness in the diffusion rates to be irrelevant by power counting in the field-theory of the contact process. However, large-scale Monte Carlo simulations demonstrate that such diffusion disorder destabilizes the clean directed percolation critical point. Instead, the transition belongs to the same infinite-randomness universality class as the contact process with disorder in the infection or healing rates. To explain these results, we develop an effective model with an infinite diffusion rate; it shows that diffusion disorder generates an effective disorder in the healing rates. The same mechanism also appears in the field-theoretic description: Whereas diffusion disorder is irrelevant by power-counting, it generates standard random-mass disorder under renormalization. We discuss the validity of this mechanism for other absorbing state transitions and non-equilibrium phase transitions in general.

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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