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arXiv 2402.06343cond-mat.stat-mechhep-thquant-ph
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恒压下的黑体热容

Blackbody heat capacity at constant pressure

E. S. Moreira

AI总结:

本文通过考虑黑体腔壁的理想导电性质,证明恒压热容、热膨胀系数和等温压缩系数在球壳与立方盒两种几何构型下均有良好定义,并揭示其热力学行为及稳定性依赖于腔体几何形状。

摘要:

乍看之下,本文标题似乎并不恰当,原因众所周知。由于黑体压强仅依赖于温度,人们无法在保持另一个量不变的情况下,对其中一个热力学量求导。也就是说,恒压热容 $C_{P}$、热膨胀系数 $α$ 以及等温压缩系数 $κ_{T}$ 都是定义不清的量。本文将表明,当考虑黑体腔壁的理想导电性质后,$C_{P}$、$α$ 和 $κ_{T}$ 实际上是定义良好的,并且它们如预期那样由通常的热力学关系相互联系。文中将考虑两种几何构型,即球壳和立方盒。将证明 $C_{P}$、$α$ 和 $κ_{T}$ 在很大程度上依赖于腔体的几何形状。还将讨论热力学稳定性问题,揭示它们同样依赖于腔体的几何形状。本文认为这些发现可能适合进行实验验证。

英文摘要:

At first glance, the title of this work seems to be improper. And the reason is well known. Since blackbody pressure depends only on temperature, one cannot take the derivative of the thermodynamic quantities with respect to one of them, keeping the other constant. That is, the heat capacity at constant pressure, $C_{P}$, as well as, the coefficient of thermal expansion, $α$, and the isothermal compressibility, $κ_{T}$, are ill-defined quantities. This work will show that when the perfect conducting nature of the walls of a blackbody cavity is taken into account, $C_{P}$, $α$ and $κ_{T}$ are in fact well defined, and they are related by the usual thermodynamic relations, as expected. Two geometries will be considered, namely, a spherical shell and a cubic box. It will be shown that $C_{P}$, $α$ and $κ_{T}$ depend very much on the geometry of the cavity. Issues regarding thermodynamic stability will be addressed, revealing that they also depend on the cavity's geometry. It is argued that these findings may be amenable to experimental verification.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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