Related papers: Constraining strongly-warped extra dimensions with…
We show that a class of four-dimensional rotating black holes allow five-dimensional embeddings as black rotating strings. Their near-horizon geometry factorizes locally as a product of the three-dimensional anti-deSitter space-time and a…
Superradiant instability turns rotating astrophysical black holes into unique probes of light axions. We consider what happens when a light axion is coupled to a strongly coupled hidden gauge sector. In this case superradiance results in an…
By using a massless scalar field we examine the effect of an extra dimension on black hole radiation. Because the equations are coupled, we find that the structure of the fifth dimension (as for membrane and induced-matter theory) affects…
After the gravity induced on the brane in the Randall-Sundrum (RS) infinite braneworld is briefly reviewed, we discuss the possibility that black holes evaporate as a result of classical evolution in this model based on the AdS/CFT…
The main focus of this lecture is on extended objects in adS*S bosonic backgrounds with unbroken supersymmetry. The backgrounds are argued to be exact, special consideration are given to the non-maximal supersymmetry case. The near horizon…
The superradiant instability of Kerr-AdS black holes is studied by numerically solving the full 3+1 dimensional Einstein equations. We find that the superradiant instability results in a two stage process with distinct initial and secondary…
We analyse the superradiant stability of braneworld extremal Kerr and Kerr-Newman black holes under massive scalar perturbation. These black hole solutions differ from their four dimensional counterpart by the presence of a tidal charge,…
We consider astrophysics of large black holes localized on the brane in the infinite Randall-Sundrum model. Using their description in terms of a conformal field theory (CFT) coupled to gravity, deduced in Ref. [1], we show that they…
We study time evolutions of charged scalar perturbations on the background of a charged hairy black hole, in which the perturbations can be governed by a double-peak effective potential. By extracting quasinormal modes from the waveform of…
Based on the hyperboloidal framework, we research the dynamical process of charged de Sitter black holes scattered by a charged scalar field. From the linear perturbation analysis, with the coupling strength within a critical interval, the…
Ultralight scalars can form superradiant clouds around rotating black holes. These may alter the dynamics of compact binaries and the ensuing waveform through orbital resonances and cloud ionization. We re-examine resonances involving…
Myers-Perry black holes with a single spin in d>5 have been shown to be unstable if rotating sufficiently rapidly. We extend the numerical analysis which allowed for that result to the asymptotically AdS case. We determine numerically the…
We study how black hole superradiance appears in string microscopic models of rotating black holes. In order to disentangle superradiance from finite-temperature effects, we consider an extremal, rotating D1-D5-P black hole that has an…
For the 2-brane Randall-Sundrum model, we calculate the bulk geometry for strong gravity, in the low matter density regime, for slowly varying matter sources. This is relevant for astrophysical or cosmological applications. The warped…
The evolution of small perturbations around rotating black branes and strings, which are low energy solutions of string theory, are investigated. For simplicity, we concentrate on the Kerr solution times transverse flat extra dimensions,…
We consider the conundrum of generating de Sitter space from higher-dimensional geometry, with particular attention to KKLT-type constructions arXiv:hep-th/0301240 and their 5d implications. We show that even in the probe approximation with…
In a universe of the Randall-Sundrum type, black holes are unstable and emit gravitational modes in the extra dimension. This leads to dramatically shortened lifetimes of astrophysical black holes and to an observable change of the orbital…
We study the dynamics of a black hole in an asymptotically $AdS_d \times S^d$ space-time in the limit of a large number of dimensions, $d \to \infty$. Such a black hole is known to become dynamically unstable below a critical radius. We…
The lowest order quantum corrections to the effective action arising from quantized massive fermion fields in the Randall-Sundrum background spacetime are computed. The boundary conditions and their relation with gauge invariance are…
Superradiant instabilities of spinning black holes can be used to impose strong constraints on ultralight bosons, thus turning black holes into effective particle detectors. However, very little is known about the development of the…