The purpose of the studies presented in this paper is to point out the need for further work towards a definitive answer to the following question: How do perturbations of a rotating black hole get radiated away? Using the Teukolsky formalism [1], we can search for an answer to that question by studying the evolution of a complex spin-weighted wavefunction that is defined in terms of curvature ...

TheKerr solution is today textbookmaterial and a basic element of education in relativity. However, derivations of it are not easy to find in the literature—most textbooks and monographs simply quote it as a given thing. There exist several uniqueness theorems (see part 2 of this note) that refer to physical and geometrical properties of the Kerr solution, but none of them gives a hint on how t...

B.M.A. (GLOUCESTERSHIRE BRANCH) Hon. Secretary: Dr. H. G. Scott-Kerr, 29 Leckhampton Road, Cheltenham 13th Oct.: Mr. J. D. J. Freeman. Presidential Address: "A Naval Opthalmolog'3' Ceylon", and a film, colour and sound, "Land of the Buddha" Gloucester. 10th Nov.: Representatives' Report. Financial Statement. Film. Cheltenham. _ ^ 8th Dec.: Guest Speaker: Mr Brian Inglis, Editor of The Spectator...

In this study, we have performed magneto-optical Kerr effect ~MOKE! measurement on epitaxial La2/3Sr1/3MnO3 thin films containing artificial interfaces created by laser-patterning the SrTiO3 substrate. The observed increase of the resistivity and of the high-field magnetoresistance when measuring the films across the interface arrays are related to the reduction of the magnetization of the inte...

In this article we study multipole moments of axisymmetric stationary asymptotically flat spacetimes. We show how the tensorial recursion of Geroch and Hansen can be reduced to a recursion of scalar functions. We also demonstrate how a careful choice of conformal factor collects all moments into one complex valued function on R, where the moments appear as the derivatives at 0. As an applicatio...

We prove the existence of a family of initial data for Einstein equations which represent small deformations of the extreme Kerr black hole initial data. The data in this family have the same asymptotic geometry as extreme Kerr. In particular, the deformations preserve the angular momentum and the area of the cylindrical end.

We consider the late-time evolution of gravitational and electromagnetic perturbations in realistic rotating Kerr spacetimes. We give a detailed analysis of the mode-coupling phenomena in rotating gravitational collapse. A consequence of this phenomena is that the late-time tail is dominated by modes which, in general, may have an angular distribution different from the original one. In additio...

We elucidate the ‘right’ process for energy extraction from Kerr black holes through ‘FFDE’ magnetospheres, free from causality violation. It is shown that the magnetosphere of a Kerr black hole possesses the double-structure, consisting of the inner and outer magnetospheres with the pair-creation gap between them and with respective unipolar batteries at the inner and outer surfaces of the gap.

In the context of the Hamiltonian formulation of the teleparallel equivalent of general relativity we compute the gravitational energy of Kerr and Kerr Anti-de Sitter (Kerr-AdS) space-times. The present calculation is carried out by means of an expression for the energy of the gravitational field that naturally arises from the integral form of the constraint equations of the formalism. In each ...