Compressible Turbulence from Quantum to Classical

需要对湍流有深入的了解，才能使聚变成为一种能源，改善超音速飞行，并解释超新星和碰撞的中子星形成金等元素的原因。尽管湍流很重要，但它的许多方面仍然没有得到很好的理解，部分原因是实验的困难：例如，研究超音速流动需要昂贵的风洞，而中子星只能间接测量。虽然通过NSF资助的LIGO等项目来研究这些系统的努力正在进行中，但冷原子技术的最新进展提供了一个在桌面实验中制造湍流的新平台。例如，超流冷原子具有非常低的音速，可以实现高超音速流动，并且具有高度的可调性，使它们能够直接对中子星的各个方面进行建模。这个项目将在这些桌面实验中的量子湍流和重要的应用之间建立联系，这些应用是对核物理、核天体物理和经典湍流正在进行的努力的补充。这些成果不仅将推动科学进步，还将确定独特的量子特征，这些特征可用于推动量子技术的未来社会利益，类似于之前冷原子技术的进步如何产生使GPS成为可能的精确时钟。该项目将探索量子和经典流体力学之间的关系，解决关于湍流的微观起源，以及为中子星建模所需的宏观流体动力学如何从微观物理中出现等问题。具体地说，它将探索这些宏观理论是如何在粗粒化量子系统之后出现的，回答如下问题：新兴理论是经典的吗(即它们是否流向类似纳维斯托克斯的固定点？)或者它们保留了独特的量子效应，可以用于新的应用？将开发出在破坏性成像的情况下检测和表征量子湍流的方法，并将与实验小组密切合作进行验证，探索沿途的新量子现象。这些经过验证的方法将被用于推进核物理，例如脉冲星毛刺的起源。这些调查需要高性能计算和复杂的数据分析技术，这将导致开源工具，广泛影响各种相关领域，并为学生提供在科学领域取得成功所需的技能。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A deep understanding of turbulence is required to enable fusion as a source of energy, improve supersonic flight, and explain the formation of elements like gold from supernovae and colliding neutron stars. Despite its importance, many aspects of turbulence are still not well understood, in part due to the difficulty of performing experiments: for example, studying supersonic flow requires expensive wind tunnels, and neutron stars can only indirectly be measured. While efforts are underway to study these systems through NSF funded programs like LIGO, recent advances in cold-atom technology provide a new platform to create turbulence in table-top experiments. For example, superfluid cold atoms have a very low speed of sound, enabling hypersonic flow, and are highly tunable, allowing them to directly model aspects of neutron stars. This project will establish a connection between quantum turbulence in these table-top experiments and important applications that complement ongoing efforts in nuclear physics, nuclear astrophysics, and classical turbulence. The outcomes will not only progress science, but will identify unique quantum features that can be used to advance quantum technologies with future societal benefit similar to how previous advances in cold atom technology produced the precision clocks that enable GPS.This project will explore the relationship between quantum and classical hydrodynamics, addressing questions about the microscopic origins of turbulence, and how the macroscopic hydrodynamics needed to model neutron stars etc. emerge from microscopic physics. Specifically, it will explore how these macroscopic theories emerge after coarse-graining quantum systems, answering questions like: Are the emergent theories classical (i.e. do they flow to a Navier-Stokes-like fixed-point?) or do they retain unique quantum effects that can be exploited for new applications? Methods will be developed for detecting and characterizing quantum turbulence in spite of destructive imaging, and will be validated in close collaboration with experimental groups, exploring new quantum phenomena along the way. These validated methods will then be used to advance nuclear physics such as the origin of pulsar glitches. These investigations require high performance computing and sophisticated data analysis techniques, which will result in open source tools, broadly impacting a variety of related fields, and provide students with the skills needed for successful careers in science.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.