活相分离:来自非平衡物理学的新现象学
1DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
概括
由于非平衡动力学,活性系统表现出独特的流体-流体相分离. 本综述探讨了如何破坏细节平衡和新的界面张力驱动这些现象,不同于平衡系统.
科学领域:
- 软物质物理学 软物质物理学
- 非平衡的统计力学 统计力学
- 活动物质理论 活动物质理论
背景情况:
- 流体-流体相分离在具有局部非平衡动态的活性系统中很常见,在生物和合成系统中看到.
- 对于平衡系统的相位分离的传统理解假定了详细的平衡,这种平衡在活性系统中是不存在的.
- 缺乏详细的平衡从根本上改变了相位分离机制,导致在平衡状态下没有观察到的现象.
研究的目的:
- 审查了解活动在流体-流体相隔离中的作用方面的最新进展.
- 要突出由非平衡动态驱动的新奇现象,例如反向奥斯瓦尔德成熟.
- 讨论主动相分离的理论框架和实验比较.
主要方法:
- 专注于连续场理论,特别是那些具有单个保存的标量顺序参数和补充速度场的理论.
- 审查这些连续理论的分析和数值研究.
- 将理论预测与基于粒子的模型和实验观测进行比较.
主要成果:
- 活相分离可以表现出明显的界面张力,包括负值,导致像反向奥斯瓦尔德成熟这样的独特现象.
- 阶段分离的现象学因在活性系统中缺乏详细平衡而发生了根本性的变化.
- 连续理论提供了一个框架来理解这些复杂的行为,与粒子模型和实验的定性协议.
结论:
- 活动引入了超出平衡预测的流体-流体相位分离的新机制和现象.
- 连续理论是研究活性物质的强大工具,尽管由于系统的复杂性,实验验证面临着挑战.
- 需要进一步的研究,以充分阐明活相分离中的多种模式和开放问题.
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