Exact axially symmetric stationary solutions of the Kaluza-Klein-Jordan-Thiry theory

1987 ◽  
Vol 36 (12) ◽  
pp. 3674-3683 ◽  
Author(s):  
William Bruckman
1991 ◽  
Vol 06 (24) ◽  
pp. 2189-2195
Author(s):  
AMIR LEVINSON ◽  
AHARON DAVIDSON

Stationary, axially symmetric solutions of Einstein equations in a free 5-dimensional Kaluza–Klein space-time are derived. The electric charge and magnetic moment are generated by a fictitious boost involving the extra dimension. The associated gyromagnetic factor tends to unity at the ultra-relativistic limit. The solution derived interpolates between the Kerr and the Belinsky–Ruffini solutions.


2021 ◽  
Vol 81 (12) ◽  
Author(s):  
Laurenţiu Bubuianu ◽  
Sergiu I. Vacaru ◽  
Elşen Veli Veliev

AbstractWe construct nonassociative quasi-stationary solutions describing deformations of Schwarzschild black holes, BHs, to ellipsoid configurations, which can be black ellipsoids, BEs, and/or BHs with ellipsoidal accretion disks. Such solutions are defined by generic off-diagonal symmetric metrics and nonsymmetric components of metrics (which are zero on base four dimensional, 4-d, Lorentz manifold spacetimes but nontrivial in respective 8-d total (co) tangent bundles). Distorted nonassociative BH and BE solutions are found for effective real sources with terms proportional to $$\hbar \kappa $$ ħ κ (for respective Planck and string constants). These sources and related effective nontrivial cosmological constants are determined by nonlinear symmetries and deformations of the Ricci tensor by nonholonomic star products encoding R-flux contributions from string theory. To generate various classes of (non) associative /commutative distorted solutions we generalize and apply the anholonomic frame and connection deformation method for constructing exact and parametric solutions in modified gravity and/or general relativity theories. We study properties of locally anisotropic relativistic, optically thick, could and thin accretion disks around nonassociative distorted BHs, or BEs, when the effects due to the rotation are negligible. Such configurations describe angular anisotropic deformations of axially symmetric astrophysical models when the nonassociative distortions are related to the outer parts of the accretion disks.


1986 ◽  
Vol 93 (1) ◽  
pp. 102-112 ◽  
Author(s):  
T. Dereli ◽  
A. Eriş ◽  
A. Karasu

2005 ◽  
Vol 20 (11) ◽  
pp. 2374-2379
Author(s):  
Y. VERBIN ◽  
A. L. LARSEN

Non-singular global cosmic strings are found in a non-linear sigma model with a potential term for a self-gravitating complex scalar field. Stationary solutions with angular momentum and possibly linear momentum are obtained by assuming an oscillatory dependence of the scalar field on t, φ and z. This dependence has an effect similar to gauging the global U(1) symmetry of the model, which is actually a Kaluza-Klein reduction from four to three spacetime dimensions. The method of analysis can be regarded as an extension of the gravito-electromagnetism formalism beyond the weak field limit.


2019 ◽  
Vol 34 (23) ◽  
pp. 1950184 ◽  
Author(s):  
Muhammad Rizwan ◽  
Muhammad Zubair Ali ◽  
Ali Övgün

In this paper, we study the tunneling of charged fermions from the stationary axially symmetric black holes using the generalized uncertainty principle (GUP) via Wentzel, Kramers, and Brillouin (WKB) method. The emission rate of the charged fermions and corresponding modified Hawking temperature of Kerr–Newman black hole, Einstein–Maxwell-dilaton-axion (EMDA) black hole, Kaluza–Klein dilaton black hole, and then, charged rotating black string are obtained and we show that the corrected thermal spectrum is not purely thermal because of the minimal scale length which cause the black hole’s remnant.


2000 ◽  
Vol 179 ◽  
pp. 379-380
Author(s):  
Gaetano Belvedere ◽  
Kirill Kuzanyan ◽  
Dmitry Sokoloff

Extended abstractHere we outline how asymptotic models may contribute to the investigation of mean field dynamos applied to the solar convective zone. We calculate here a spatial 2-D structure of the mean magnetic field, adopting real profiles of the solar internal rotation (the Ω-effect) and an extended prescription of the turbulent α-effect. In our model assumptions we do not prescribe any meridional flow that might seriously affect the resulting generated magnetic fields. We do not assume apriori any region or layer as a preferred site for the dynamo action (such as the overshoot zone), but the location of the α- and Ω-effects results in the propagation of dynamo waves deep in the convection zone. We consider an axially symmetric magnetic field dynamo model in a differentially rotating spherical shell. The main assumption, when using asymptotic WKB methods, is that the absolute value of the dynamo number (regeneration rate) |D| is large, i.e., the spatial scale of the solution is small. Following the general idea of an asymptotic solution for dynamo waves (e.g., Kuzanyan & Sokoloff 1995), we search for a solution in the form of a power series with respect to the small parameter |D|–1/3(short wavelength scale). This solution is of the order of magnitude of exp(i|D|1/3S), where S is a scalar function of position.


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