Related papers: Charge extraction from a black hole
Photon charge has been of interest as a phenomenological testing ground for basic assumptions in fundamental physics. There have been several constraints on the photon charge based on very different considerations. In this paper we put…
We study a rotating black hole with anisotropic matter and electromagnetic fields. We show that the electromagnetic field has the same form as the corresponding one in the Kerr-Newman geometry. The reason is thanks to the specific form of…
We discuss the problem of the third black hole parameter, an electric charge. While the mass and the spin of black holes are frequently considered in the majority of publications, the charge is often neglected and implicitly set identically…
We propose a method for measuring the black hole charge by imaging a black hole shadow in a galactic center by future interferometers. Even when the black hole is uncharged, it is possible to confirm the charge neutrality by this method. We…
Though a black hole can theoretically possess a very big charge ($Q/(\sqrt{G} M) \simeq 1$), the charge of the real astrophysical black holes is usually considered to be negligible. This supposition is based on the fact that an…
The generalization of the black hole in three-dimensional spacetime to include an electric charge Q in addition to the mass M and the angular momentum J is given. The field equations are first solved explicitly when Q is small and the…
We obtain non-extremal charged rotating black holes in six-dimensional SU(2) gauged supergravity with two independent angular momenta and one U(1) charge. These include supersymmetric black holes without naked closed timelike curves.
It is an interesting open problem whether two non-extremal rotating and electrically charged black holes can be in physical equilibrium, which might be possible due to a balance between the gravitational attraction and the spin-spin and…
Current astrophysical observations show that on large scale the Universe is electrically neutral. However, locally this may be quite different. Black holes enveloped by a plasma in the presence of a strong magnetic field may have acquired a…
It is shown that the non-Abelian black hole solutions have stationary generalizations which are parameterized by their angular momentum and electric Yang-Mills charge. In particular, there exists a non-static class of stationary black holes…
The scattering cross sections of the unpolarized electromagnetic and gravitational waves are shown to be equal for the extreme Reissner-Nordstr\"om black hole using $N=2$ supergravity. The conversion cross sections between the unpolarized…
We present improved estimates of the electric charge that black holes could hold when these are embedded in the ionised plasma within galaxies. We have implemented the spontaneous emission of charges of opposite sign to that of the black…
We proposed a gravitational energy momentum tensor in previous paper. By using it, we evaluate an electric and a gravitational energies in and out of an event horizon of a charged black hole. There is no gravitational energy in the event…
We present a novel solution describing four dimensional rotating regular charged black hole in the low energy heterotic string theory. This present solution is characterized by its mass, charged, as well as angular momentum. Some aspect…
We study the scattering of axially incident massless scalar waves by a charged and rotating black hole solution from heterotic string theory called the Kerr-Sen black hole. We compute the scattering cross section using the partial wave…
We argue that states with nontrivial horizontal charges of BTZ black hole can be excited by ordinary falling matter including Hawking radiation. The matter effect does not break the integrability condition of the charges on the horizon.…
Black holes can be electromagnetically charged, or carry vector charge from new fundamental fields. Their response to small fluctuations is of paramount importance to study gravitational wave generation. However, the usual even and odd…
We compute the absorption cross section and the total power carried by gravitons in the evaporation process of a higher-dimensional non-rotating black hole. These results are applied to a model of extra dimensions with standard model fields…
The mass--energy formula of black holes implies that up to 50% of the energy can be extracted from a static black hole. Such a result is reexamined using the recently established analytic formulas for the collapse of a shell and expression…
If photon mass is not exactly zero, though arbitrary small, electric charge would not be conserved in interaction of charged particles with black holes. Manifestations of such mechanism of electric charge non-conservation are discussed.