Theoretical study of soft matter systems

软物质是一个涉及物理学、化学、生物学和材料科学的交叉学科。它研究的物理系统，可以相对容易地变形，以响应外部和内部的物理和化学条件。实例包括胶体、聚合物、凝胶、液晶和若干生物系统。这些材料与传统的固态材料竞争，有时甚至优于传统的固态材料。软物质理论由诺贝尔奖赢家皮埃尔-吉勒·德·热内（Pierre-Gilles de Gennes）等先驱创立，是一个在过去半个世纪在基础和应用研究方面都有巨大新发展的领域。 该提案提出了一个全面的软物质理论研究计划，集成了一些重要的和具有挑战性的问题，涉及聚合物，膜和液晶。在我们的理论处理中，一个共同点是在研究这些系统时使用统计物理学。一些新的方向包括：Flory-Huggins相互作用能和半柔性聚合物熔体的不可压缩性条件的框架的发展，其中取向依赖性是重要的，Rayleigh不稳定性在定义带电囊泡的构象中的相关性，由嵌入颗粒上的波动聚合物密度引起的Casimir力的开始，囊泡移位动力学，囊泡制表和珠光动力学，DNA包装结构，缺陷液晶态之间的转换动力学，和限制中的液晶聚合物。基于这一提议的令人兴奋的发现将大大推进对软物质的基本理解-构建明天新材料的操场。*** 在过去的10年里，我的研究小组已经开发出了尖端的工具，可以很容易地利用这些工具来解决这些新的方向。它们包括：蠕虫状聚合物链的自洽场理论，基于流体表面三角测量的三维囊泡建模，液晶系统的密度泛函模型，以及基于Wang-Landau型权重的Monte Carlo模拟。通过其明确的设计，这个多方面的研究计划非常适合培养硕士和博士水平的研究生和博士后研究员。这些研究问题将在智力上挑战我的研究小组，因此训练有素的HQP将在学术和工业研究中产生重大影响。*** **

Soft matter is a cross disciplinary research field involving physics, chemistry, biology, and materials science. It studies physical systems that can be deformed relatively easily in response to external and internal physical and chemical conditions. Examples include colloids, polymers, gels, liquid crystals, and several biological systems. These materials compete with and sometimes outperform the traditional solid-state materials. Founded by pioneers such as Nobel Prize winner Pierre-Gilles de Gennes, soft matter theory is a field that has seen vast new developments in the last half century, in both fundamental and applied research.****     This proposal presents a comprehensive soft-matter-theory research program that integrates a number of important and challenging problems involving polymers, membranes, and liquid crystals. In our theoretical treatment, a common ground is the use of statistical physics in studying these systems. Some new directions include: the development of a framework for the Flory-Huggins interaction energy and incompressibility condition of semiflexible polymer melts consisting of molecules for which the orientational dependence is importance, the relevance of Rayleigh instability in defining the conformation of charged vesicles, the onset of Casimir force caused by fluctuating polymer densities on embedded particles, vesicle translocation kinetics, vesicle tabulation and pearling dynamics, DNA packing structure, transition kinetics between defect liquid-crystal states, and liquid-crystal polymers in confinement. The exciting discoveries based on this proposal will significantly advance the fundamental understanding of soft matter --- a playground for constructing new materials of tomorrow. ***      Over the last 10 years, my research group has developed cutting-edge tools that can be readily exploited to tackle these new directions. They include: the self-consistent field theory for wormlike polymer chains, three-dimensional vesicle modeling based on triangulation of a fluid surface, density-functional models for liquid-crystal systems, and Monte Carlo simulations based on Wang-Landau type weights. By its explicit design, this multifaceted research program is ideally suited for training MSc- and PhD-level graduate students and postdoctoral fellows. The research problems will intellectually challenge my research group hence the trained HQP in their pathways to make substantial impact in academic and industrial research. *** **