Noise-Induced Phase Transitions

传统上，噪声被认为是干扰物理系统“有趣的”或“内在的”行为的“麻烦”。在过去的二十年里，这种有限的观点忽略了噪音实际上可以增强甚至引起理想行为的工具方式，这一点已经变得非常清楚，但是这种方式的发生仍然是大量研究的基础。在这个项目中，我们专注于这样一个戏剧性的现象，即空间扩展系统中噪声诱导的相变。这些是宏观的转变，噪声不仅使系统从一个相位到另一个相位，而且相位的存在是基于噪声的存在；如果没有它，系统只能存在于一个阶段。研究将尝试系统地探索导致噪声诱导相变的基本特征，这些相变与随机共振等噪声诱导信号增强现象的相互作用，设计参数的控制和适应性，以产生具有所需特性的噪声诱导相位，以及允许可视化空间分布的噪声非线性系统的用户友好界面的开发。

Noise has traditionally been thought of as a "Nuisance" that interferes with the "interesting" or "intrinsic" behavior of physical systems. That this limited view misses the instrumental ways in which noise can actually enhance and even cause desirable behaviors has become quite clear in the past two decades, but the ways in which this can occur are still grounds for fertile investigation. In this project we focus on one such dramatic phenomenon, that of noise-induced phase transitions in spatially extended systems. These are macroscopic transitions where the noise not only causes the system to go from one phase to another, but where the very existence of the phases is predicated on the presence of the noise; in its absence the system can only exist in one phase. The investigations will attempt to systematically explore the basic features that lead to noise-induced phase transitions, the interplay of these transitions with noise-induced signal enhancement phenomena such as stochastic resonance, the control and adaptability of design parameters to produce noise-induced phases with desired properties, and the development of user-friendly interfaces that allow visualization of spatially distributed noisy nonlinear systems.