How and Why Fish School: An Information-theoretic Analysis of Coordinated Swimming

该补助金将支持那些将贡献与流体-结构相互作用和集体动力学相关的新知识的研究，促进科学进步和技术进步。在没有可靠的数学模型的情况下，迫切需要在复杂的流体-结构相互作用的分析和固体之间的流体耦合的诊断方面取得进展。工程和科学领域的关键例子包括人类发声、对阵风做出反应的高大土木结构群、用于水下传感的活性材料阵列、碳纳米管纳米垫、用于流体混合和运输的纤毛阵列以及桡足类动物的触角刚毛。该奖项支持基础研究，以填补这些知识空白，重点是鱼类集群，其能源效率，几何复杂性和视觉吸引力已经吸引了科学界和公众几个世纪的兴趣。这项研究涉及几个学科桥接数据驱动的动力系统，实验流体力学和实验生物学。多学科方法在正式和非正式学习中发挥着重要作用，通过培训来自代表性不足群体的大学生，让来自贫困社区的高中生接触生物学，工程学和数学，并向公众推广。最近的实验结果表明，在足够大的游泳速度下，鱼群可能更喜欢以“方阵”的形式游泳，在那里没有领头的鱼，每一条鱼都几乎同步地拍打着它们的尾巴。从经典的钻石形成的方阵挑战目前的理解的漩涡相互作用的鱼集群，这可能会被其他流体动力学或视觉途径取代的作用。然而，目前还不可能严格测试这种可能性，因为缺乏数据驱动的技术来区分协调游泳的原因和影响。该项目将提供一种基于实验原理的方法来量化动力系统集合中的信息流，通过涉及不同传播时间和物理变量的多个路径进行交互。假设驱动的，工程原理的实验将被进行，以发现和探索支撑协调游泳的动态结构，信息通路和能量机制。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This grant will support research that will contribute new knowledge related to fluid-structure interactions and collective dynamics, promoting the progress of science and empowering technological advancements. There is a dire need for advancements in the analysis of complex fluid-structure interactions and in the diagnostics of fluid coupling between solids, without having access to reliable mathematical models. Critical examples across engineering and science include human phonation, clusters of tall civil structures reacting to wind gusts, arrays of active materials for underwater sensing, nanomats of carbon nanotubes, arrays of cilia for fluid mixing and transport, and antennulary setal hairs of copepods. This award supports fundamental research to fill these gaps in knowledge, focusing on fish schooling, whose energy efficiency, geometric complexity, and visual allure have attracted the interest of the scientific community and general public for centuries. This research involves several disciplines bridging data-driven dynamical systems, experimental fluid mechanics, and experimental biology. The multi-disciplinary approach carries momentum in formal and informal learning, by training University students from underrepresented groups, exposing high school students from underprivileged communities to biology, engineering, and mathematics, and outreach to the general public.Recent experimental results demonstrate that at sufficiently large swimming speeds, schooling fish may prefer to swim in a "phalanx" formation, where there is no leader and every fish beats their tail almost in synchrony. The transition from the classical diamond formation to the phalanx challenges the present understanding of the role of vortex interactions in fish schooling, which might be superseded by other hydrodynamic or visual pathways. Yet, it is currently impossible to rigorously test this possibility, due to the lack of data-driven techniques to disentangle causes from effects in coordinated swimming. This project will contribute a mathematically-principled, experimentally-grounded approach to quantify information flow in ensembles of dynamical systems, interacting through multiple pathways that involve varying propagation times and physical variables. Hypothesis-driven, engineering-principled experiments will be conducted toward the discovery and exploration of dynamic structure, information pathways, and energetic mechanisms that underpin coordinated swimming.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.