Related papers: Black Strings and p-Branes are Unstable
We develop the perturbation theory for R^2 string-corrected black hole solutions in d dimensions. After having obtained the master equation and the alpha'-corrected potential under tensorial perturbations of the metric, we study the…
The Standard Model is the low-energy limit of a microscopic theory which includes extra dimensions and new symmetries. A part of my thesis consisted in constructing a new class of models with two extra dimensions. We showed that these…
We investigate the stability of a new warped black string with nontrivial topologies in five-dimensional Anti-de Sitter spacetime. After studying the linear gravitational perturbation, we find that this black string is unstable when the…
We study evolution of gravitational perturbations of black strings. It is well known that for all wavenumber less than some threshold value, the black string is unstable against scalar type of gravitational perturbations, which is named the…
Combining toric geometry techniques and $\mathcal{N}=2$ supergravity formalisms, we study 5D black branes in the M-theory compactification on a four parameter Calabi-Yau threefold. First, we investigate 5D BPS and non-BPS black holes that…
We construct new configurations of oppositely charged, static black hole pairs (diholes) in four dimensions which are solutions of low energy string/M-theory. The black holes are extremal and have four different charges. We also consider…
We generalize the vacuum static black strings with negative cosmological constant recently discussed in literature, by including an electromagnetic field. These higher-dimensional configurations have no dependence on the `compact' extra…
We study aspects of four dimensional black holes with two electric charges, corresponding to fundamental strings with generic momentum and winding on an internal circle. The perturbative \alpha' correction to such black holes and their…
We present a new set of analytic solutions of general relativity with a negative cosmological constant, which describe black strings and black p-branes in arbitrary number of dimensions, $D$. The solutions are supported by minimally…
The perturbations of string-theoretic black holes are analyzed by generalizing the method of Chandrasekhar. Attention is focussed on the case of the recently considered charged string-theoretic black hole solutions as a representative…
All the models of elementary particles and their interactions derived from String Theory involve a compact six-dimensional internal space. Its volume and shape should be fixed or stabilized, since otherwise massless scalar fields (moduli)…
We study the evolution of cosmic strings taking into account the frictional force due to the surrounding radiation. We consider small perturbations on straight strings, oscillation of circular loops and small perturbations on circular…
Black holes, the simplest solution to Einstein's field equations, do not emit light, making their observations a major challenge for researchers. However, discovery of binary black holes (BBHs) in 2015 by LIGO has transformed the study of…
We discuss special supersymmetric extreme black holes in 4 and 5 dimensions which have regular horizons, non-zero entropy and can be interpreted as compactifications of BPS bound states of p-branes in 10 or 11 dimensions.
We construct uniform black-string solutions in Einstein-Gauss-Bonnet gravity for all dimensions $d$ between five and ten and discuss their basic properties. Closed form solutions are found by taking the Gauss-Bonnet term as a perturbation…
In this paper, some dynamical properties of neutral and charged particles around a weakly magnetized five-dimensional static black string have been studied. The perturbation method was also used to calculate the Innermost Stable Circular…
We examine the thermodynamic stability of large black holes in four-dimensional anti-de Sitter space, and we demonstrate numerically that black holes which lack local thermodynamic stability often also lack stability against small…
Analytic form has been obtained for four-dimensional black holes with a minimal Hawking temperature in a theory with cosmological constant, dilaton and gauge fields. In general dimensions, black hole solutions are shown to exist and their…
We study linear massive scalar charged perturbations of Topological Stars in the fuzzball and in the black hole (Black String) regimes. The objects that naturally couple to the electric 3-form field strength of these solutions are charged…
Black holes have their proper oscillations, which are called the quasi-normal modes. The proper oscillations of astrophysical black holes can be observed in the nearest future with the help of gravitational wave detectors. Quasi-normal…