Classical properties of non-local, ghost- and singularity-free gravity
Classical properties of non-local, ghost- and singularity-free gravity
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DOI：
10.1088/1475-7516/2018/09/034
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发表时间：
2018-02
影响因子：
6.4
通讯作者：
L. Buoninfante;A. Koshelev;G. Lambiase;A. Mazumdar
中科院分区：
文献类型：
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作者：
L. Buoninfante;A. Koshelev;G. Lambiase;A. Mazumdar
本文给出了引力无穷导数鬼理论和无奇性理论在静态极限下的所有线性化曲率张量。我们发现，在非定域区域，在紫外区（离源很近），Ricci张量和Ricci标量并没有消失，这意味着我们不再有Ricci平坦真空解，这是由于非定域引力相互作用的存在引起的源的涂抹。这也表明，与爱因斯坦的引力不同，黎曼张量不是无迹的，它与外尔张量不一致。其次，这些曲率在短距离处被正则化，使得它们是无奇异性的，特别是对于Kretschmann不变量也是如此。与其他的不同，外尔张量在短距离处消失，这意味着时空度规在紫外非定域区域接近共形平坦。我们简要地讨论了在非线性政权的解决方案，并认为，1/r度规势不能在短距离政权的解决方案，非局部性变得重要。
In this paper we will show all the linearized curvature tensors in the infinite derivative ghost and singularity free theory of gravity in the static limit. We have found that in the region of non-locality, in the ultraviolet regime (at short distance from the source), the Ricci tensor and the Ricci scalar are not vanishing, meaning that we do not have a Ricci flat vacuum solution anymore due to the smearing of the source induced by the presence of non-local gravitational interactions. It also follows that, unlike in Einstein's gravity, the Riemann tensor is not traceless and it does not coincide with the Weyl tensor. Secondly, these curvatures are regularized at short distances such that they are singularity-free, in particular the same happens for the Kretschmann invariant. Unlike the others, the Weyl tensor vanishes at short distances, implying that the spacetime metric approaches conformal-flatness in the region of non-locality, in the ultraviolet. We briefly discuss the solution in the non-linear regime, and argue that 1/r metric potential cannot be the solution in the short-distance regime, where non-locality becomes important.