Two innovative equivalent statements of the third law of thermodynamics  

作　　者：陈晓航 周颖慧 陈金灿 Xiaohang Chen;Yinghui Zhou;Jincan Chen(Department of Physics,Xiamen University,Xiamen 361005,China)

机构地区：[1]Department of Physics,Xiamen University,Xiamen 361005,China

出　　处：《Chinese Physics B》2024年第6期324-328,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 12075197);the Fundamental Research Fund for the Central Universities of China (Grant No. 20720210020)。

摘　　要：It is found from textbooks and literature that there are three different statements for the third law of thermodynamics,i.e., the Nernst theorem, the unattainability statement of absolute zero temperature, and the heat capacity statement. It is pointed out that such three statements correspond to three thermodynamic parameters, which are, respectively, the entropy,temperature, and heat capacity, and can be obtained by extrapolating the experimental results of different parameters at ultralow temperatures to absolute zero. It is expounded that because there is no need for additional assumptions in the derivation of the Nernst equation, the Nernst theorem should be renamed as the Nernst statement. Moreover, it is proved that both the Nernst statement and the heat capacity statement are mutually deducible and equivalent, while the unattainability of absolute zero temperature is only a corollary of the Nernst statement or the heat capacity statement so that it is unsuitably referred to as one statement of the third law of thermodynamics. The conclusion is that the Nernst statement and the heat capacity statement are two equivalent statements of the third law of thermodynamics.

关 键 词：Nernst statement heat capacity statement Nernst theorem absolute zero temperature the third law of thermodynamics 

分 类 号：O414.11[理学—理论物理]