论文标题
FRW宇宙的热力学：热发动机
Thermodynamics of FRW Universe: Heat Engine
论文作者
论文摘要
我们假设非平原弗里德曼·罗伯逊 - 沃克（FRW）宇宙是热力学系统。我们将宇宙学视野视为内部诱捕范围，被视为FRW宇宙的动态视野。我们在明显的地平线上写下了动态的明显范围和温度。我们假设流体压力是系统的热力压力。使用Hayward的统一第一定律，Clausius关系和具有宇宙常数的Friedmann方程，我们在明显的地平线上获得了熵。我们假设宇宙常数提供了系统的热力压力。我们获得熵，表面积，体积，温度，GIBB的Helmholtz的自由能，由于热力学系统而引起的FRW宇宙的比热容量。我们研究了FRW宇宙的焦耳 - 汤姆森（Joule-Thomson）的扩展，并通过评估焦耳 - 汤姆森（Joule-Thomson）系数的积极迹象，我们确定FRW宇宙遵守冷却性质。我们还发现反转温度和反转压力。接下来，我们将热力学FRW宇宙作为热发动机展示。对于Carnot周期，我们获得完成的工作和最大效率。同样对于新引擎，我们研究完成的工作及其效率。
We assume the non-flat Friedmann-Robertson-Walker (FRW) Universe as a thermodynamical system. We assume the cosmological horizon as a inner trapping horizon which is treated as dynamical apparent horizon of FRW Universe. We write the dynamical apparent horizon radius and temperature on the apparent horizon. We assume that the fluid pressure as thermodynamical pressure of the system. Using Hayward's unified first law, Clausius relation and Friedmann equations with cosmological constant, we obtain the entropy on the apparent horizon. We assume that the cosmological constant provides the thermodynamic pressure of the system. We obtain the entropy, surface area, volume, temperature, Gibb's Helmholtz's free energies, specific heat capacity of the FRW Universe due to the thermodynamic system. We study the Joule-Thomson expansion of the FRW Universe and by evaluating the positive sign of Joule-Thomson coefficient, we determine that the FRW Universe obeys the cooling nature. We also find the inversion temperature and inversion pressure. Next we demonstrate the thermodynamical FRW Universe as heat engine. For Carnot cycle, we obtain the work done and the maximum efficiency. Also for new engine, we study the work done and its efficiency.
