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arXiv 2006.01513gr-qc
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球对称圈量子引力:改进的动力学分析

Spherically symmetric loop quantum gravity: analysis of improved dynamics

R. Gambini, J. Olmedo, J. Pullin

摘要:

本文研究了Chiou { \em et al.}提出的圈量子引力中球对称时空的“改进动力学”。类似于Ashtekar,Pawlowski和Singh为均匀时空构建的模型。在这种动力学中,聚合参数是动力学变量的良好动机函数,反映了面积量子依赖于它们的事实。与均匀情况相反,其实施不会触发不期望的物理性质。我们在量子理论中识别了半经典物理态,并导出了相应的有效半经典度规。然后我们讨论了它们的一些性质。具体地说,时空在低曲率下足够快地接近史瓦西几何。此外,在经典理论中的奇异性区域被一个规则的但离散的有效几何所取代,该有效几何具有有限的普朗克阶曲率,而与黑洞的质量无关。这避免了在量子化方案中出现的天体物理学黑洞的反普朗克曲率,而没有改进。它使得奇点的分辨率更符合在模型中观察到的一个,该模型使用史瓦西黑洞内部的等距与Kantowski-Sachs圈量子宇宙学。人们可以观察到,在黑洞内部出现了对零能量条件的有效违反,这是奇点消除机制的一部分。

英文摘要:

We study the "improved dynamics" for the treatment of spherically symmetric space-times in loop quantum gravity introduced by Chiou {\em et al.} in analogy with the one that has been constructed by Ashtekar, Pawlowski and Singh for the homogeneous space-times. In this dynamics the polymerization parameter is a well motivated function of the dynamical variables, reflecting the fact that the quantum of area depends on them. Contrary to the homogeneous case, its implementation does not trigger undesirable physical properties. We identify semiclassical physical states in the quantum theory and derive the corresponding effective semiclassical metrics. We then discuss some of their properties. Concretely, the space-time approaches sufficiently fast the Schwarzschild geometry at low curvatures. Besides, regions where the singularity is in the classical theory get replaced by a regular but discrete effective geometry with finite and Planck order curvature, regardless of the mass of the black hole. This circumvents trans-Planckian curvatures that appeared for astrophysical black holes in the quantization scheme without the improvement. It makes the resolution of the singularity more in line with the one observed in models that use the isometry of the interior of a Schwarzschild black hole with the Kantowski--Sachs loop quantum cosmologies. One can observe the emergence of effective violations of the null energy condition in the interior of the black hole as part of the mechanism of the elimination of the singularity.

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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