We calculate the structure of accretion disc around a rapidly rotating black hole with a super-Eddington accretion rate. The luminosity and height of the disc are reduced by the advection effect. In the case of a large viscosity parameter, α > 0.03, the accretion flow strongly deviates from thermodynamic equilibrium and overheats in the central region. With increasing accretion rate, the flow t...

The capture or scattering of an initially straight infinite test cosmic string by a Kerr-Newman black hole, or by any other small source of an electrovac gravitational field, is analyzed analytically when the string moves with initial velocity v 0 and large impact parameter z 0 = b ≫ M so that the string stays very nearly straight (except during the final capture process, if that occurs, or exc...

Download Massive complex scalar field in the Kerr–Sen geometry: Exact solution of wave equation and Hawking radiation S. Q. Wu Interdisciplinary Center for Theoretical Study, and Department of Astronomy and Applied Physics, University of Science and Technology, Hefei 230026, People’s Republic of China and Institute of Particle Physics, Hua-Zhong Normal University, Wuhan 430079, People’s Republi...

We derive the system of equations describing the time dependent twisted accretion disc around a Kerr black hole (twist equations). The post-Newtonian corrections to the equations of motion and effects of the gravitomagnetic force are taken into account. We show that introduction of appropriate coordinate system greatly simplifies the derivation of equations and allows to consider sufficiently l...

We discuss different classes of van Stockum spacetimes which are stationary and axisymmetric spacetimes of dust rotating rigidly on trajectories of the time translation Killing vector. The flow has no Newtonian limit. Asymptotically flat solutions are not physically viable. As an example we construct a sequence of asymptotically flat internal multipolar solutions. The corresponding sequence of ...

Title of dissertation: THE OPTICAL KERR EFFECT OF LIQUIDS Xiang Zhu, Doctor of Philosophy, 2007 Dissertation directed by: Professor John T. Fourkas Department of Chemistry and Biochemistry Optical Kerr effect (OKE) spectroscopy has found broad use in monitoring ultrafast dynamics in transparent media. I demonstrated that by using two pump pulses with independently-controllable polarizations, in...

optic properties of uranium-based compounds" Uranium-based compounds often show interesting magnetic properties and large polar Kerr rotations. Because of this, the wavelength and temperature dependencies of the polar Kerr rotation in several uranium-based compounds, including UMnzGez, UFe2, and UGa2, have been investigated. The Mn moments order ferromagnetically in UMnzGel below 380 K, and whi...

Geometrical properties of the extreme Kerr black holes in the topological sectors of nonextreme and extreme configurations are studied. We find that the Euler characteristic plays an essential role to distinguish these two kinds of extreme black holes. The relationship between the geometrical properties and the intrinsic thermodynamics

The Regge-Wheeler equation describes axial perturbations of Schwarzschild metric in linear approximation. Teukolsky Master Equation describes perturbations of Kerr metric in the same approximation. We present here unified description of all classes of exact solutions to these equations in terms of the confluent Heun’s functions. Special attention is paid to the polynomial solutions, which yield...

Biswas and Milovic proposed a generalized model for the NLSE that accounts for several imperfections in the fiber during long distance transmission of these pulses. This paper studies the exact solution of the BiswasMilovic equation with Kerr law nonlinearity by a new efficient method. The results reveal that the method is explicit, effective, and easy to use.