Spatio-Temporal Chaos in Systems of Broken Symmetry

这个实验项目将继续研究扩展动力系统中的非线性、非平衡模式形成现象。令人感兴趣的系统是在两个平行板之间的加压气体中发现的热对流。这个系统和许多其他系统一样，呈现出空间和时间相关性迅速下降的非瞬时状态。这些复杂的状态被称为时空混沌(STC)，近年来受到了极大的关注。这个项目中解决的一个悬而未决的问题是如何与STC互动，甚至控制STC。这项研究将解决热对流如何对空间和时空强迫做出反应。将采用两种类型的强制方案。第一种是使用康奈尔大学纳米制造设施制造的微加工表面，第二种是热压印技术。对STC的更好了解可能会潜在地影响物理、生物和医学等基础科学领域，但也会影响应用领域，如加热技术、材料加工等。实验结果还将为在超级计算机上解决流体力学问题而开发的数值代码提供基准。调查包括与W.Pesch教授(德国)和Steve Lipson(以色列)的国际合作。此外，还将继续与太平洋大学的理查德·维纳合作。参与该项目和这个研究小组的研究生接受从微制造、机械和电子系统设计到数字图像处理等尖端实验技术方面的培训。这一经验为研究生提供了学术、工业和政府职业生涯的培训和准备。本实验研究计划继续调查在两个平行板之间的加压气体中的热驱动流动中发生的图案形成。这些图案在光学上是可见的，因为气体中的自发密度波动。该项目将研究流动显示高度无序对流模式的情况。这样的情况在日常生活中也会发生；例如天空中的条纹云纹或风沙的一些重复图案。这些复杂图案的动力学是当前的重大科学兴趣。这项研究计划将解决的一个重要问题是如何与这些在空间和时间上都是混乱的状态相互作用，甚至控制它们。这项研究计划将通过使用康奈尔大学纳米制造设施制造的微机械表面和使用热压印技术来解决这个问题。更好地了解这些时空混沌状态及其控制可以在物理学、生物学和医学(如心脏颤动、癫痫)等基础科学以及加热技术、材料加工等技术方面产生影响。该研究包括与W.Pesch教授(德国)和Steve Lipson(以色列)的国际合作。此外，还将继续与太平洋大学的理查德·维纳合作。参与该项目和这个研究小组的研究生接受从微制造、机械和电子系统设计到数字图像处理等尖端实验技术方面的培训。这一经历为研究生提供了在学术界、工业界和政府部门就业的培训和准备。

This experimental project will continue investigations of non-linear, non-equilibrium pattern-forming phenomena in extended dynamical systems. The system of interest is thermal convection found in pressurized gases confined between two parallel plates. This system, and many others, exhibits non-transient states in which spatial and temporal correlations fall off quickly. These complex states are termed "Spatio-Temporal Chaos"(STC), and have received much attention in recent years. An open question addressed in this project, is how to interact with or even control STC. The research will address how thermal convection responds to spatial and spatio-temporal forcing. Two types of forcing schemes will be applied. The first uses micro-machined surfaces that are manufactured at Cornell's Nano Fabrication Facility, the second a thermal imprinting technique. Better knowledge of STC may potentially impact fundamental science areas such as physics, biology, and medicine, but also applied areas, like heating technology, materials processing, etc. The experimental results will also provide a benchmark for numerical codes developed for solving hydrodynamical problems on supercomputers. The investigation includes an international collaboration with Prof. W. Pesch (Germany) and Steve Lipson (Israel). In addition, a collaboration with Richard Wiener from Pacific University will be continued. Graduate students involved in the project and in this research group receive training in cutting edge experimental techniques ranging from microfabrication, design of mechanical and electronic systems, to digital image processing. This experience provides graduate students with training and preparation for careers in academe, industry, and government.This experimental research program continues an investigation into the pattern formation that occurs in thermally driven flows in pressurized gases confined between two parallel plates. The patterns are visible optically as spontaneous density fluctuations in the gas. The project will examine situations where the flow shows highly disordered convection patterns. Such situations also occur in everyday life; an example is striped cloud-streaks in the sky or in the somewhat repetitive patterns of windblown sand. The dynamics of these complex patterns is significant current scientific interest. An important question that will be addressed in this research program is how to interact with or even control these states that are chaotic both in space and time. This research program will address this question by using micro-machined surfaces that are manufactured at Cornell's Nano Fabrication Facility and by using thermal imprinting techniques. A better knowledge of these spatio-temporal chaotic states and their control can have an impact in both fundamental science, like physics, biology, and medicine (as in cardiac fibrillation, epilepsy), as well as in technology, like heating technology, materials processing, etc. The investigation includes an international collaboration with Prof. W. Pesch (Germany) and Steve Lipson (Israel). In addition, a collaboration with Richard Wiener from Pacific University will be continued. Graduate students involved in the project and in this research group receive training in cutting edge experimental techniques ranging from microfabrication, design of mechanical and electronic systems, to digital image processing. This experience provides graduate students with training and preparation for careers in academe, industry, and government.