Caravelli Francesco, Sheldon Forrest C, Traversa Fabio L
Theoretical Division (T4), Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Sci Adv. 2021 Dec 24;7(52):eabh1542. doi: 10.1126/sciadv.abh1542. Epub 2021 Dec 22.
Simple elements interacting in networks can give rise to intricate emergent behaviors. Examples such as synchronization and phase transitions often apply in many contexts, as many different systems may reduce to the same effective model. Here, we demonstrate such a behavior in a model inspired by memristors. When weakly driven, the system is described by movement in an effective potential, but when strongly driven, instabilities cause escapes from local minima, which can be interpreted as an unstable tunneling mechanism. We dub this collective and nonperturbative effect a “Lyapunov force,” which steers the system toward the global minimum of the potential function, even if the full system has a constellation of equilibrium points growing exponentially with the system size. This mechanism is appealing for its physical relevance in nanoscale physics and for its possible applications in optimization, Monte Carlo schemes, and machine learning.
在网络中相互作用的简单元素能够产生复杂的涌现行为。诸如同步和相变等例子在许多情境中都适用,因为许多不同的系统可能会简化为相同的有效模型。在此,我们在一个受忆阻器启发的模型中展示了这样一种行为。当受到弱驱动时,系统由在有效势中的运动来描述,但当受到强驱动时,不稳定性会导致从局部最小值逃逸,这可被解释为一种不稳定的隧穿机制。我们将这种集体且非微扰的效应称为“李雅普诺夫力”,它能引导系统趋向势函数的全局最小值,即便整个系统具有随着系统规模呈指数增长的一系列平衡点。这种机制因其在纳米尺度物理学中的物理相关性以及在优化、蒙特卡罗方法和机器学习中的可能应用而颇具吸引力。