Physics of Living Tangled Matter

打结和缠绕的丝状结构是生命系统和人类技术的标志，从DNA到编织。相比之下，能够自主自组装、分解和破坏对称性的纠缠活性物质的设计原理目前尚不清楚。首席研究员(PI)建议通过研究活节和缠结的物理学来探索材料科学和应用数学的这一新前沿。这项研究是由于PI发现了相互缠绕在一起的复杂的拓扑图案形成柔软的斑点的黑虫(Lumbrulus Varegatus)。这些水滴可以聚集、变形、吞噬、运输货物，并迅速溶解。这些斑点代表了一个独特的打结的生物材料的例子，它使用拓扑力学来产生紧急的、智能的行为，这在其他已知材料中是没有的。在这些蠕虫迷人的行为的激励下，在这个奖项中，PI将使用数学理论来构建最小的纠缠和解缠状态，从而能够控制拓扑结构。PI将开发实验技术和低维表示法来表征蠕虫斑点作为一种拓扑可调材料。PI还将开发将缠绕蠕虫作为活动细丝的多物理模型，将缠绕纤维的物理属性(如能量和弹性扭矩)与拓扑参数(如连接、扭结和交叉数)联系起来。最后，PI将开发控制方案和统一的相图，用于预测纠缠系综中的形状变形和对称破坏。有了这个奖项，PI对生命纠缠和结的物理学的跨学科研究有可能影响到广泛的领域，包括数学、材料科学、生物和物理。除了增进我们对生命系统的理解外，这项工作还可能在刺激反应材料、生物织物和变形机器人的开发方面取得突破，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。为了让历史上被边缘化的社区更多地参与到这项研究中来，PI计划让所有级别的年轻科学家参与、指导和教育，从K-12到博士后。这一奖项反映了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。

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.