We propose a quasi-local stress tensor for the four-dimensional asymptotically flat Robinson-Trautman geometries by taking the flat-space limit from the corresponding asymptotically AdS solutions. This stress tensor results in the correct charges of the generators of BMS symmetry if we define conformal infinity by an anisotropic scaling of the metric components. Using flat-space holography this stress tensor is related to expectation values of the stress tensor in a dual field theory called BMS-invariant field theory (BMSFT). We also calculate the two and three point functions of the proposed stress tensor.
In our previous paper [Phys. Rev. D 89 (2014) 124029], cited as [1], we attempted to find Robinson-Trautman-type solutions of Einstein's equations representing gyratonic sources (matter field in the form of an aligned null fluid, or particles propagating with the speed of light, with an additional internal spin). Unfortunately, by making a mistake in our calculations, we came to the wrong conclusion that such solutions do not exist. We are now correcting this mistake. In fact, this allows us to explicitly find a new large family of gyratonic solutions in the Robinson-Trautman class of spacetim…
We discuss the holographic reconstruction of four-dimensional asymptotically anti-de Sitter Robinson-Trautman spacetime from boundary data. We use for that a resummed version of the derivative expansion. The latter involves a vector field, which is interpreted as the dual-holographic-fluid velocity field and is naturally defined in the Eckart frame. In this frame the analysis of the non-perfect holographic energy-momentum tensor is considerably simplified. The Robinson-Trautman fluid is at rest and its time evolution is a heat-diffusion kind of phenomenon: the Robinson-Trautman equation plays …
We summarize recent results on $D$-dimensional Robinson-Trautman solutions of Einstein's gravity in the presence of a conformally invariant non-linear electromagnetic field and a cosmological constant. These spacetimes contain static dyonic black holes with various horizon geometries and their time-dependent radiating generalizations, as well as a class of stealth solutions. Extensions to $f(R)$ and Gauss-Bonnet gravity are mentioned.
We present the Riemann and Ricci tensors for a fully general non-twisting and shear-free geometry in arbitrary dimension D. This includes both the non-expanding Kundt and expanding Robinson-Trautman family of spacetimes. As an interesting application of these explicit expressions we then integrate the Einstein equations and prove a surprising fact that in any D the Robinson-Trautman class does not admit solutions representing gyratonic sources, i.e., matter field in the form of a null fluid (or particles propagating with the speed of light) with an additional internal spin. Contrary to the clo…
Université libre de Bruxelles（布鲁塞尔自由大学）；International Solvay Institutes（国际索尔维研究所）；School of Quantum Physics and Matter Institute for Research in Fundamental Sciences (IPM)（基础科学研究所量子物理与物质学院）
Static and radiating p-form black holes in the higher dimensional Robinson-Trautman class
本文研究了在n ≥ 4维空间中，存在一个p型麦克斯韦场和一个任意宇宙学常数的Robinson-Trautman时空.事实证明，这些精确解的性质在很大程度上取决于n和p的（相对）值。在奇数维中，解简化为被电场和磁场装扮的静态黑洞，其视界是爱因斯坦空间（进一步受到爱因斯坦-麦克斯韦方程组的约束）--外尔和麦克斯韦类型都是D。然而，即使是维度，也开辟了更多的可能性。特别地，当2 p =n时，存在描述黑洞通过接收（或发射）电磁辐射获得（或失去）质量的非静态解。在这种情况下，外尔型是II（D），麦克斯韦型可以是II（D）或N。条件下的麦克斯韦场是自对偶（奇p）进行了讨论，并提出了一些明确的例子。最后，p=1的情况在所有维度上都是特殊的，并导致具有非爱因斯坦横向空间的静态度量。
Gravitational Memory Beyond Null Infinity through Finite-Distance Carrollian Screens
Facultad de Ingeniería, Universidad San Sebastián（圣塞巴斯蒂安大学工程学院）；Department of Physics and Astronomy, University of Waterloo（滑铁卢大学物理与天文学系）；Perimeter Institute for Theoretical Physics（理论物理前沿研究所）；Departamento de Física, Universidad de Concepción（康塞普西翁大学物理系）
We investigate the complete family of (aligned) Robinson-Trautman spacetimes sourced by conformally invariant non-linear electrodynamics in $D$ dimensions in the presence of an arbitrary cosmological constant. After presenting general features of the solutions (which exist only in even dimensions), we discuss in more detail some particular subclasses. Static metrics contain dyonic black holes with various possible horizon geometries (Kähler if there is a magnetic field, including flat branes) and different asymptotics. In addition, there exist also time-dependent solutions (not possible in the…
We show that a holographic description of four-dimensional asymptotically locally flat spacetimes is reached smoothly from the zero-cosmological-constant limit of anti-de Sitter holography. To this end, we use the derivative expansion of fluid/gravity correspondence. From the boundary perspective, the vanishing of the bulk cosmological constant appears as the zero velocity of light limit. This sets how Carrollian geometry emerges in flat holography. The new boundary data are a two-dimensional spatial surface, identified with the null infinity of the bulk Ricci-flat spacetime, accompanied with …
Tsinghua University（清华大学）；Perimeter Institute for Theoretical Physics（理论物理前沿研究所）；Lomonosov Moscow State University（罗蒙诺索夫莫斯科国立大学）；The Chinese University of Hong Kong（香港中文大学）
