2021/10/01 by Amir Hadi Ziaie, A. H. Ziaie, H. Moradpour +1
Mathematics · Physics and Astronomy · #Apparent horizon #Black Holes and Theoretical Physics #Classical mechanics #Context (archaeology) #Cosmology and Gravitation Theories #Curvature #Equation of state #Event horizon #General relativity #Geometry #Gravitation #Gravitational collapse #Mathematics #Noncommutative and Quantum Gravity Theories #Physics #Quantum mechanics #Singularity #Spacetime #physics.gen-ph
paper · pdf · doi:10.1140/epjp/s13360-021-02082-8
published as European Physical Journal Plus, 136, 1085 (2021) · 10 Pages & 5 Figures
openalex publication_date 2021/10/01 · arxiv created 2021/10/29 · arxiv updated 2021/11/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In the present work we study spherically symmetric gravitational collapse of a homogeneous perfect fluid in the context of Generalized Rastall Theory (GRT). In this modified version of the original Rastall Gravity (RG), the coupling parameter which is a representative of matter-curvature interaction is no longer a constant parameter. Such a dynamic coupling may play the role of dark energy which is responsible for the present accelerating expansion of the Universe. Assuming then a linear equation of state (EoS) for the fluid profiles, we seek for physically reasonable collapse scenarios in which the spacetime singularity that occurs in general relativity (GR) is replaced by a non-singular bounce. We therefore find that depending on model parameters, the collapse process which starts from regular initial data, will halt at a minimum value for the scale function and then turns into an expansion at a finite time. We further find that there exists a minimum value for the initial radius of collapsing object so that for radii smaller than this minimum radius, formation of apparent horizon can be avoided and hence the bounce can be visible to the observers within the Universe. We also compare our results to quantum corrected collapse scenarios and find that the mutual interaction between matter and geometry can play the role of quantum corrections to energy density.