Black Holes Coupled to Time-Dependent Scalar Fields in the Kaluza-Klein Theory

Abstract Kaluza–Klein theory is a popular alternative theory of gravity, with both non-rotating and rotating black hole solutions known. This allows for the possibility that the theory could be observationally tested. We present a model which calculates the reflection spectrum of a black hole accretion disk system, where the black hole is described by a rotating solution of the Kaluza–Klein theory. We also use this model to analyze X-ray data from the stella-mass black hole in GRS 1915+105 and provide constraints on the free parameters of the Kaluza–Klein black holes.

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MASSLESS SCALAR FIELDS IN NON-ABELIAN KALUZA-KLEIN THEORY

International Journal of Modern Physics A ◽

10.1142/s0217751x94000248 ◽

1994 ◽

Vol 09 (04) ◽

pp. 507-515 ◽

Cited By ~ 1

Author(s):

M. ARIK ◽

V. GABAY

Keyword(s):

Cosmological Constant ◽

Direct Product ◽

Scalar Fields ◽

Gauge Fields ◽

Internal Space ◽

Massless Scalar ◽

Klein Theory ◽

Euler Form ◽

Odd Dimensions ◽

Kaluza Klein

We investigate the presence of massless scalar fields in a Kaluza—Klein theory based on a dimensionally continued Euler-form action. We show that massless scalar fields exist provided that the internal space is a direct product of two irreducible manifolds. The condition of a vanishing effective four-dimensional cosmological constant and the presence of a graviton, gauge fields and massless scalar fields can be satisfied if both irreducible manifolds have odd dimensions and the sum of these dimensions is equal to the dimension of the Euler form.

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ON TIME-DEPENDENT BLACK HOLES AND COSMOLOGICAL MODELS FROM A KALUZA–KLEIN MECHANISM

International Journal of Modern Physics A ◽

10.1142/s0217751x09042931 ◽

2009 ◽

Vol 24 (07) ◽

pp. 1383-1415

Author(s):

C. CASTRO ◽

J. A. NIETO ◽

L. RUIZ ◽

J. SILVAS

Keyword(s):

Black Holes ◽

Black Hole ◽

Cosmological Model ◽

Black Hole Entropy ◽

Time Dependent ◽

Einstein Field Equations ◽

Schwarzschild Black Hole ◽

Field Equations ◽

Newman Black Hole ◽

Kaluza Klein

Novel static, time-dependent and spatial–temporal solutions to Einstein field equations, displaying singularities, with and without horizons, and in several dimensions, are found based on a dimensional reduction procedure widely used in Kaluza–Klein-type theories. The Kerr–Newman black hole entropy as well as the Reissner–Nordstrom, Kerr and Schwarzschild black hole entropy are derived from the corresponding Euclideanized actions. A very special cosmological model based on the dynamical interior geometry of a black hole is found that has no singularities at t = 0 due to the smoothing of the mass distribution. We conclude with another cosmological model equipped also with a dynamical horizon and which is related to Vaidya's metric (associated with the Hawking radiation of black holes) by interchanging t ↔ r, which might render our universe a dynamical black hole.

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MULTIDIMENSIONAL GEOMETRICAL MODEL OF THE RENORMALIZED ELECTRICAL CHARGE WITH SPLITTING OFF THE EXTRA COORDINATES

Modern Physics Letters A ◽

10.1142/s021773239800231x ◽

1998 ◽

Vol 13 (27) ◽

pp. 2179-2185 ◽

Cited By ~ 20

Author(s):

V. D. DZHUNUSHALIEV

Keyword(s):

Black Holes ◽

Electric Charge ◽

Geometrical Model ◽

Electrical Charge ◽

Wormhole Solution ◽

Flux Lines ◽

Klein Theory ◽

Real Relation ◽

Null Surfaces ◽

Kaluza Klein

A geometrical model of electric charge is proposed. This model has "naked" charge screened with a "fur-coat" consisting of virtual wormholes. The 5-D wormhole solution in the Kaluza–Klein theory is the "naked" charge. The splitting off of the 5-D happens on the two spheres (null surfaces) bonding this 5-D wormhole. This allows one to sew two Reissner–Nordström black holes onto it on both sides. The virtual wormholes entrap a part of the electrical flux lines coming into the "naked" charge. This effect essentially changes the charge visible at infinity so that it satisfies the real relation m2<e2.

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Stationary black holes with time-dependent scalar fields

Physical Review D ◽

10.1103/physrevd.90.041501 ◽

2014 ◽

Vol 90 (4) ◽

Cited By ~ 31

Author(s):

Alexander A. H. Graham ◽

Rahul Jha

Keyword(s):

Black Holes ◽

Scalar Fields ◽

Time Dependent

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A Kaluza–Klein subtractor

Modern Physics Letters A ◽

10.1142/s0217732314500795 ◽

2014 ◽

Vol 29 (16) ◽

pp. 1450079 ◽

Cited By ~ 1

Author(s):

Sanjib Jana ◽

Chethan Krishnan

Keyword(s):

Black Holes ◽

Exact Solutions ◽

Equations Of Motion ◽

Specific Class ◽

Attraction Basin ◽

Rotating Black Holes ◽

Klein Theory ◽

Attraction Basins ◽

Extremal Black Holes ◽

Kaluza Klein

We generalize the results of arXiv:1212.1875 and arXiv:1212.6919 on attraction basins and their boundaries to the case of a specific class of rotating black holes, namely the ergo-free branch of extremal black holes in Kaluza–Klein theory. We find that exact solutions that span the attraction basin can be found even in the rotating case by appealing to certain symmetries of the equations of motion. They are characterized by two asymptotic parameters that generalize those of the non-rotating case, and the boundaries of the basin are spinning versions of the (generalized) subtractor geometry. We also give examples to illustrate that the shape of the attraction basin can drastically change depending on the theory.

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