Junction conditions in infinite derivative gravity

In a recent approach in modeling a radiating relativistic star undergoing gravitational collapse the role of the Weyl stresses was emphasized. It is possible to generate a model which is physically reasonable by approximately solving the junction conditions at the boundary of the star. In this paper we demonstrate that it is possible to solve the Einstein field equations and the junction conditions exactly. This exact solution contains the Friedmann dust solution as a limiting case. We briefly consider the radiative transfer within the framework of extended irreversible thermodynamics and show that relaxational effects significantly alter the temperature profiles.

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Kodama-Schwarzschild versus Gaussian Normal Coordinates Picture of Thin Shells

Advances in High Energy Physics ◽

10.1155/2016/5632734 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Mikhail Z. Iofa

Keyword(s):

Spherical Shell ◽

Coordinate Transformation ◽

Time Dependent ◽

Thin Shells ◽

Junction Conditions ◽

Coordinate Systems ◽

Normal Coordinate ◽

Normal Coordinates

Geometry of the spacetime with a spherical shell embedded in it is studied in two coordinate systems: Kodama-Schwarzschild coordinates and Gaussian normal coordinates. We find explicit coordinate transformation between the Kodama-Schwarzschild and Gaussian normal coordinate systems. We show that projections of the metrics on the surface swept by the shell in the 4D spacetime in both cases are identical. In the general case of time-dependent metrics we calculate extrinsic curvatures of the shell in both coordinate systems and show that the results are identical. Applications to the Israel junction conditions are discussed.

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Towards nonsingular rotating compact object in ghost-free infinite derivative gravity

Physical Review D ◽

10.1103/physrevd.98.084041 ◽

2018 ◽

Vol 98 (8) ◽

Cited By ~ 24

Author(s):

Luca Buoninfante ◽

Alan S. Cornell ◽

Gerhard Harmsen ◽

Alexey S. Koshelev ◽

Gaetano Lambiase ◽

...

Keyword(s):

Compact Object ◽

Infinite Derivative

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Junction conditions on surface layers for radiating fluid spheres with heat flow

Physics Letters A ◽

10.1016/0375-9601(89)90792-5 ◽

1989 ◽

Vol 138 (1-2) ◽

pp. 1-4 ◽

Cited By ~ 4

Author(s):

L. Herrera ◽

J. Ibáñez

Keyword(s):

Heat Flow ◽

Junction Conditions ◽

Surface Layers ◽

Fluid Spheres

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Five-dimensional spherical gravitational collapse of anisotropic fluid with cosmological constant

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887817500256 ◽

2017 ◽

Vol 14 (02) ◽

pp. 1750025 ◽

Cited By ~ 4

Author(s):

Suhail Khan ◽

Hassan Shah ◽

Ghulam Abbas

Keyword(s):

Cosmological Constant ◽

Apparent Horizon ◽

Physical Significance ◽

Anisotropic Fluid ◽

Spherically Symmetric ◽

Hole Size ◽

Junction Conditions ◽

De Sitter ◽

Positive Cosmological Constant ◽

Exterior Regions

Our aim is to study five-dimensional spherically symmetric anisotropic collapse with a positive cosmological constant (PCC). For this purpose, five-dimensional spherically symmetric and Schwarzschild–de Sitter metrics are chosen in the interior and exterior regions respectively. A set of junction conditions is derived for the smooth matching of interior and exterior spacetimes. The apparent horizon is calculated and its physical significance is studied. It comes out that the whole collapsing process is influenced by the cosmological constant. The collapsing process under the influence of cosmological constant slows down and black hole size also reduced.

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Some analytic models of plane symmetric radiating collapse

Canadian Journal of Physics ◽

10.1139/cjp-2016-0518 ◽

2017 ◽

Vol 95 (1) ◽

pp. 65-68 ◽

Cited By ~ 1

Author(s):

G. Abbas ◽

Hassan Shah ◽

Zahid Ahmad

Keyword(s):

Thermal Behavior ◽

Analytical Solutions ◽

Adiabatic Index ◽

Junction Conditions ◽

Matter Distribution ◽

Field Equations ◽

Plane Symmetric ◽

Symmetric Source ◽

The Stability ◽

Analytic Models

This paper deals with the analytical solutions of the field equations in the presence of radiating plane symmetric source. For this purpose we have solved the field equations as well as junction conditions by imposing the conformal flatness conditions. The effective adiabatic index (that determines the stability of the system) has been calculated for the present radiating source. It has been found that effective adiabatic index remains invariant throughout the matter distribution. To study the thermal behavior of the source, we have discussed the thermal profile of the source and found that in the absence of dissipation from the system the temperature of the system remains constant.

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