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在有序的极性活性流体中相分离:与平衡流体完全不同的普遍性类别
1Department of Physics and Institute for Fundamental Science, <a href="https://ror.org/0293rh119">University of Oregon</a>, Eugene, Oregon 97403, USA.
Physical review. E
|December 18, 2024
概括
活性流体中的相位分离产生了明显的高密度和低密度波段. 这项研究揭示了它属于一个新的普遍性类,不同于平衡流体相隔离.
科学领域:
- 物理 物理学 物理
- 软物质物理学 软物质物理学
- 统计力学 统计力学
背景情况:
- 自行实体,如群体或极性顺序的活性流体,表现出集体运动.
- 吸引力相互作用可以在这些系统中诱导相位分离,从而导致不同的密度带.
- 了解活性物质的相位分离对于理解新出现的行为至关重要.
研究的目的:
- 研究阶段分离在有序极性活性流体中的普遍性类.
- 为了确定这种过渡是否不同于平衡流体中的相位分离.
- 计算密度和速度波动的临界指数和缩量定律.
主要方法:
- 动态重新规范化组分析.
- 使用d=5-ε扩展来计算关键指数.
- 分析大距离,长时间的缩放规律.
主要成果:
- 在有序的极性活性流体中,相分离属于一种新的普遍性类.
- 上临界维度是d_{c}=5,不同于平衡系统 (d_{c}=4).
- 波动的通用临界指数 (ν_{},ν_{},β) 得到了O.
结论:
- 活性流体中的相位分离代表了一个新的普遍性类.
- 这一发现挑战了对凝聚物质相变的现有范式.
- 计算的指数提供了对活性物质集体行为的定量见解.
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