Quantum Coherences, Fluctuations and Chaos

在经典动力学的宏观世界中，混沌是指对起始或初始条件的极端敏感性。当混乱占主导地位时，就会产生重要的结果，例如所有不同解决方案的可能性相等。这些，反过来，在我们对自然统计理论的长期行为的理解中，重新审视了许多悬而未决的问题。即使是这种简单的混沌观也不能很好地适用于微观世界或量子世界，因为它们是由波动效应主导的。干涉和衍射效应抑制了对初始条件的经典灵敏度，导致首选构型。这些效应被统称为量子混沌，包括非均匀性甚至在经典描述中存在的特征。一般来说，混沌和规则或稳定区域共存，这种“混合空间”动力学的量子结果知之甚少。这一机制也与最近不同寻常的一系列实验有关，这些实验是在各种各样的新环境中进行的。提出的研究将继续进行混合空间量子相干的表征工作，并详细分析其对环境噪声的鲁棒性。数值与解析相结合的方法专门针对原子光学作为实验测试平台。预计这些发现将有助于澄清经典描述和量子描述能够协调一致的条件

***9800966Sundaram In the macroscopic world of classical dynamics, chaos refers to an extreme sensitivity to the starting or initial condition. When chaos is dominant important consequences, such as the equal likelihood of all distinct solutions, result. These, in turn, revisit many unanswered questions in our understanding of the long-time behavior of statistical theories of nature. Even this simple view of chaos does not carry over well to the microscopic or quantum world, which is dominated by wave effects. Interference and diffraction effects suppress the classical sensitivity to initial conditions and result in preferred configurations. Collectively referred to as quantum chaos, these effects multiply on including the feature that non-uniformities exist even in the classical description. In general, chaotic and regular or stable regions coexist and the quantum consequences of this `mixed space' dynamics are poorly understood. This regime is also pertinent to a recent, and unusual, confluence of experiments in a variety of novel contexts. The proposed study continues with ongoing work on the characterization of the mixed space quantum coherences as well as a detailed analysis of their robustness to environmental noise. The combination numerical and analytic method specifically targets atom optics as the experimental test bed for the findings. It is anticipated that the findings will help clarify the conditions under which the classical and quantum descriptions can be reconciled.***