Physics of Living Tangled Matter

从DNA到编织，结结和纠结的丝状结构是生命系统和人类技术的标志。相比之下，纠缠活性物质的设计原理，可以自主自组装，拆卸，打破对称目前尚不清楚。首席研究员（PI）建议通过研究活结和缠结的物理学来探索材料科学和应用数学的新前沿。这项研究之所以成为可能，是因为PI发现了黑虫（Lumbriculus variegatus），它们以复杂的拓扑模式相互缠绕，形成柔软的斑点。这些斑点可以聚集、变形、吞噬、运输货物，并迅速溶解。这些斑点代表了一种独特的结状生物材料，它利用拓扑力学产生了在其他已知材料中未见的紧急智能行为。受到这些蠕虫迷人行为的激励，在这个奖项中，PI将使用数学理论来构建最小的缠结和解缠状态，从而实现对拓扑结构的控制。PI将开发实验技术和低维表示来表征蠕虫团作为拓扑可调材料。PI还将开发作为活动细丝的缠结蠕虫的多物理模型，将缠结纤维的物理特性（如能量和弹性扭矩）与拓扑参数（如链接、扭动和交叉数）联系起来。最后，PI将开发控制方案和统一相图，用于预测缠结集成中的形状变形和对称破缺。有了这个奖项，PI对活缠结和结的物理学的跨学科研究有可能影响广泛的领域，包括数学、材料科学、生物学和物理学。除了推进我们对生命系统的理解，这项工作还可能导致刺激响应材料、活织物和形状变形机器人的发展取得突破，这些机器人可以在深海或火星等具有挑战性的环境中航行。为了增加历史上被边缘化的群体对这项研究的参与，PI计划让从K-12到博士后的各个层次的年轻科学家都参与进来，并对他们进行指导和教育。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Knotted and tangled filamentous structures are hallmarks of living systems and human technologies, from DNA to weaving. By contrast, design principles for tangled active matter that can autonomously self-assemble, disassemble, and break symmetry are currently unknown. The Principal Investigator (PI) proposes to explore this new frontier of materials science and applied mathematics by studying the physics of living knots and tangles. This research is made possible by the PI's discovery of blackworms (Lumbriculus variegatus) that intertwine with each other in complex, topological patterns to form soft blobs. These blobs can aggregate, shape-shift, engulf, transport cargo, and dissolve rapidly. The blobs represent a unique example of a knotted living material that uses topological mechanics to produce emergent, intelligent behavior, not seen in other known materials.Motivated by the fascinating behavior of these worms, in this award the PI will use mathematical theory to construct minimal tangling and untangling states that enable control over the topological structure. The PI will develop experimental techniques and low-dimensional representation to characterize the worm blob as a topologically tunable material. The PI will also develop multi-physics models of tangling worms as active filaments, linking physical properties of tangled fibers, such as energy and elastic torque, to topological parameters such as link, writhe, and crossing number. Finally, the PI will develop control schemes and unifying phase diagrams for predictive shape-morphing and symmetry-breaking in tangled ensembles.With this award, the PI's interdisciplinary research on the physics of living tangles and knots has the potential to impact a wide range of fields, including mathematics, materials science, biology, and physics. Beyond advancing our understanding of living systems, this work could also lead to breakthroughs in the development of stimuli-responsive materials, living fabrics, and shape-morphing robots that could navigate challenging environments like the deep ocean or Mars. To increase the participation of historically marginalized communities in this research, the PI plans to involve, mentor, and educate young scientists at all levels, from K-12 to postdocs.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.