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小而简单的系统有利于时间的箭头
1Department of Physics, Arizona State University, Tempe, AZ 85287-1504, USA.
Entropy (Basel, Switzerland)
|March 28, 2024
概括
热力学第二定律,即不可逆转的增长,即使在小,简单的系统中也可以出现. 这一发现需要内在不可逆转的微观动力学,挑战系统复杂性的假设.
科学领域:
- 热力学是一种热力学.
- 统计力学 统计力学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 热力学第二定律规定,向热平衡的不可逆转的增加.
- 这种不可逆转性往往被认为是需要由可逆的微观物理学产生的大型,复杂的系统.
研究的目的:
- 为了研究是否不可逆转的的增加可以出现在小,简单的系统.
- 测试一个假设,即热力学不可逆转性需要复杂的系统.
主要方法:
- 使用模拟和理论分析的1D环的N Ising旋转.
- 将旋转系统合到N个爱因斯坦振荡器的显式热浴中.
- 计算旋转和热浴的精确,改变动态从可逆到不可逆.
主要成果:
- 在热力学极限中观察到的热平衡行为.
- 在小到N=2.2的系统中证明了热平衡行为.
- 这两种结果都取决于内在不可逆转的微观动力学.
结论:
- 热力学不可逆转性和平衡可以在非常小的系统中表现出来.
- 不可逆性的出现并不本质上需要大型系统大小或复杂性.
- 本质上不可逆转的微观动力学对于观察这些现象至关重要.
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