We analyse the impact of positivity conditions on static spherically symmetric deformations of the Schwarzschild space-time. The metric is taken to satisfy, at least asymptotically, the Einstein equation in the presence of a non-trivial stress-energy tensor, on which we impose various physicality conditions. We systematically study and compare the impact of these conditions on the space-time deformations. The universal nature of our findings applies to both classical and quantum metric deformations with and without event horizons. We further discuss minimal realisations of the asymptotic stress energy tensor in terms of physical fields. Finally, we illustrate our results by discussing concrete models of quantum black holes.
Cosmological consequences of generalised RS II braneworlds
我们讨论了宇宙学的某些功能,在一个广义RS II braneworld的情况。在这种情况下,体积是由一个Schwarzschild-anti de Sitter或Vaidya-anti de Sitter黑洞给出的,其中FRW膜始终嵌入其中,导致四维弗里德曼方程的修改。我们分析了如何可以可视化的情况下,并讨论在这些修改后的方程的早期和晚期的宇宙学的每个术语的意义。我们进一步分析的扰动方程,牛顿以及相对论性扰动的基础上,并表明,该方案有可能解释结构形成的“Weyl流体”所产生的嵌入几何。这样得到的结果也与观测结果相对照。
Conservation laws and flux bounds for gravitational perturbations of the Schwarzschild metric
本文导出了双零规范下史瓦西时空中引力微扰系统的能量守恒定律。由此产生的身份只涉及一阶导数的度量扰动。利用出现的通量边界项的规范不变性,我们能够建立任何输出零超曲面上的通量到初始数据的未来的正性。这使我们能够根据初始数据来约束通过任何这样的超曲面的总能量通量,包括事件视界。同样,我们将辐射的总能量限制在零无穷大。我们的估计提供了一个直接的方法,以弱形式的稳定性,从而补充证明的完全线性稳定的Schwarzschild解决方案最近得到的[M。达费莫斯湾霍尔泽格尔和我。Rodnianski \emph{The linear stability of the Schwarzschild solution to gravitational perturbations},arXiv:1601.06467].
Buchdahl stars and bounds with cosmological constant
University College London(伦敦大学学院);University of KwaZulu-Natal(夸祖鲁-纳塔尔大学);Inter University Centre for Astronomy & Astrophysics(大学天文学与天体物理中心);University of Science and Technology of China(中国科学技术大学)
Boundary-induced corrections to the response of an Unruh-DeWitt detector outside a compact star with Robin surface conditions
Institute of Theoretical Physics, National University of Uzbekistan(乌兹别克斯坦国立大学理论物理研究所);University of Tashkent for Applied Sciences(塔什干应用科学大学);Kimyo International University in Tashkent(塔什干化学国际大学);School of Physics, Harbin Institute of Technology(哈尔滨工业大学物理学院);Institute for Advanced Studies, New Uzbekistan University(新乌兹别克斯坦大学高级研究院)