Surface gravity in spherically symmetric collapsing stars

Abstract

Here we consider the generalized Oppenheimer-Snyder collapse of a star into a four-dimensional Einstein-Gauss-Bonnet black hole as well as a class of regular black holes labeled by the polytropic index of the stellar matter. We then analyze the nature of the horizon and the corresponding surface gravity outside and inside the star. The Hayward and Nielsen-Visser dynamical surface gravity are in agreement with the one resulting from the Killing vector of the outer static metric. However, these two definitions inside the star do not coincide with the Killing surface gravity outside the star when the star crosses the event horizon. This motivates us to study the surface gravity using Fodor's approach to have a unique surface gravity at the mentioned moment. Then the extremality condition and the first law of thermodynamics are discussed at the trapping horizon of the star.

arXiv comment13 pages, 2 figures, accepted for publication in EPJC

References in corpus (25)

• Introduction to Modified Gravity and Gravitational Alternative for Dark Energy
• Formation and evaporation of non-singular black holes
• General Laws of Black-Hole Dynamics
• Einstein-Gauss-Bonnet gravity in 4-dimensional space-time
• Unified first law of black-hole dynamics and relativistic thermodynamics
• Wormhole geometries in f(R) modified theories of gravity
• Alternatives to Dark Matter and Dark Energy
• Generalized curvature-matter couplings in modified gravity
• Dynamical Horizons: Energy, Angular Momentum, Fluxes and Balance Laws
• Black hole boundaries
• On Taking the $D\to 4$ limit of Gauss-Bonnet Gravity: Theory and Solutions
• Wormhole geometries supported by a nonminimal curvature-matter coupling
• Derivation of Regularized Field Equations for the Einstein-Gauss-Bonnet Theory in Four Dimensions
• Production and decay of evolving horizons
• A general class of braneworld wormholes
• General class of wormhole geometries in conformal Weyl gravity
• Marginally trapped tubes and dynamical horizons
• Kodama time: Geometrically preferred foliations of spherically symmetric spacetimes
• Dynamical surface gravity
• Black holes and black hole thermodynamics without event horizons
• Surface gravity in dynamical spherically symmetric spacetimes
• Dynamical Surface Gravity in Spherically Symmetric Black Hole Formation
• Generalized Oppenheimer-Snyder Gravitational Collapse into Regular Black holes
• On the gravitational collapse in 4-dimensional Einstein-Gauss-Bonnet gravity
• Brane worlds and dark matter