有效的大法典描述了阴性温度状态下冷凝的情况
Stefano Iubini1,2, Antonio Politi1,3
1Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, via Madonna del Piano 10, I-50019 Sesto Fiorentino, Italy.
Physical review letters
|March 25, 2025
概括
开放系统中的负温度状态是超稳定的,随着负温度的增加,寿命呈指数增长. 这一发现为统计力学和凝结过程提供了新的见解.
科学领域:
- 统计力学 统计力学
- 量子物理学 量子物理学 是一种量子物理学.
- 非线性动力学是一种非线性动力学.
背景情况:
- 负温度状态挑战了传统的统计力学.
- 这些状态在大法典系统中是不稳定的.
- 了解它们在开放系统中的行为至关重要.
研究的目的:
- 在开放系统中研究负温度状态的稳定性和寿命.
- 为它们的超稳定性制定一个理论框架.
- 探索保存定律在凝结过程中的作用.
主要方法:
- 在开放式设置中分析离散的非线性施罗丁格方程.
- 为非相互作用的粒子开发一个简化的随机模型.
- 探究基不变数对系统动态的影响.
主要成果:
- 负温度状态在开放系统中是超稳定的.
- 它们的寿命 (τ) 呈现出对负温度的指数依赖 (τ≈exp(λ
- 为 λ 衍生出一个通用表达式,在离散非线性施罗丁格模型中增强了附加变量不变量.
结论:
- 负温度状态的元稳定性为凝结提供了新的视角.
- 保护法对动态的结有很大影响,并延长了状态的寿命.
- 这项工作将理论统计力学与非线性系统中的可观测现象联系起来.
相关概念视频
Phase Transitions: Vaporization and Condensation
17.0K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase...
17.0K
Adiabatic Processes for an Ideal Gas
3.0K
When an ideal gas is compressed adiabatically, that is, without adding heat, work is done on it, and its temperature increases. In an adiabatic expansion, the gas does work, and its temperature drops. Adiabatic compressions actually occur in the cylinders of a car, where the compressions of the gas-air mixture take place so quickly that there is no time for the mixture to exchange heat with its environment. Nevertheless, because work is done on the mixture during the compression, its...
3.0K
Phase Transitions: Sublimation and Deposition
16.6K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
16.6K
Pressure and Volume in an Adiabatic Process
2.6K
Free expansion of a gas is an adiabatic process. However, there are few differences between free expansion and adiabatic expansion. During free expansion, no work is done, and there is no change in internal energy. But, for an adiabatic expansion, work is done, and there is a change in internal energy. During an adiabatic process, the relation between the pressure and volume is obtained from the condition for the adiabatic process, that is,
2.6K
pV-Diagrams
3.9K
The pV diagram, which is a graph of pressure versus volume of the gas under study, is helpful in describing certain aspects of the substance. When the substance behaves like an ideal gas, the ideal gas equation describes the relationship between its pressure and volume. On a pV diagram, it is common to plot an isotherm, which is a curve showing p as a function of V with the number of molecules and the temperature fixed. Then, for an ideal gas, the product of the pressure of the gas and its...
3.9K
Zeroth Law of Thermodynamics
4.6K
Experimentally, if object A is in equilibrium with object B, and object B is in equilibrium with object C, then object A is in equilibrium with object C. That statement of transitivity is called the "zeroth law of thermodynamics." For example, a cold metal block and a hot metal block are both placed on a metal plate at room temperature. Eventually, the cold block and the plate will be in thermal equilibrium. In addition, the hot block and the plate will be in thermal equilibrium.
4.6K


