Samarjit Chakraborty, Sunil D Maharaj, Sarbari Guha and Rituparno Goswami
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引用次数: 0
摘要
我们研究了导热和辐射能量的流体的球形坍缩情况下时间引力箭头的状况。我们特别研究了 W. B. Bonnor 在其 1985 年论文中获得的结果,他发现引力时间箭头与热力学时间箭头相反。波纳尔使用的引力纪元函数 P 的度量是由韦尔平方与利玛窦平方之比给出的。在本文中,我们假定引力熵(GE)的度量 P1 是由韦尔标量与克雷奇曼标量之比给出的。我们的分析表明,波诺的结果似乎得到了验证,即时间的引力箭头和热力学箭头指向相反的方向。这加强了我们的观点,即韦尔提出的GE只适用于整个宇宙(前提是我们排除白洞)。
Arrow of time and gravitational entropy in collapse
We investigate the status of the gravitational arrow of time in the case of a spherical collapse of a fluid that conducts heat and radiates energy. In particular, we examine the results obtained by W. B. Bonnor in his 1985 paper where he found that the gravitational arrow of time was opposite to the thermodynamic arrow of time. The measure of gravitational epoch function P used by Bonnor was given by the ratio of the Weyl square to the Ricci square. In this paper, we have assumed the measure of gravitational entropy (GE) P1 to be given by the ratio of the Weyl scalar to the Kretschmann scalar. Our analysis indicates that Bonnor’s result seems to be validated, i.e. the gravitational arrow and the thermodynamic arrow of time point in opposite directions. This strengthens the opinion that the Weyl proposal of GE applies only to the Universe as a whole (provided that we exclude the white holes).
期刊介绍:
Classical and Quantum Gravity is an established journal for physicists, mathematicians and cosmologists in the fields of gravitation and the theory of spacetime. The journal is now the acknowledged world leader in classical relativity and all areas of quantum gravity.