English

Bouncing behavior in $f(R,L_m)$ gravity: Phantom crossing and energy conditions

General Relativity and Quantum Cosmology 2024-03-29 v1 Cosmology and Nongalactic Astrophysics

Abstract

In this work, we investigate the bouncing behavior of the universe within the framework of f(R,Lm)f(R,L_m) gravity, using a simple form of f(R,Lm)=R2+Lmγf(R,L_m)=\frac{R}{2}+L_m^\gamma (where γ\gamma is a free model parameter) as previously studied. The model predicts a vanishing Hubble parameter in the early and late times, with the deceleration parameter approaching a specific limit at the bouncing point. The EoS parameter is observed to cross the phantom divide line (ω=1\omega=-1) near the bouncing point, indicating a significant transition from a contracting to an expanding phase. The model satisfies the necessary energy conditions for a successful bouncing scenario, with violations indicating exotic matter near the bouncing point. Stability conditions are satisfied for certain values of γ\gamma near the bouncing point, but potential instabilities in late-time evolution require further investigation. Finally, we conclude that the f(R,Lm)f(R,L_m) gravity model is promising for understanding the universe's dynamics, especially during events like the bouncing phase.

Keywords

Cite

@article{arxiv.2403.15772,
  title  = {Bouncing behavior in $f(R,L_m)$ gravity: Phantom crossing and energy conditions},
  author = {M. Koussour and N. Myrzakulov and Javlon Rayimbaev and Alnadhief H. A. Alfedeel and H. M. Elkhair},
  journal= {arXiv preprint arXiv:2403.15772},
  year   = {2024}
}

Comments

International Journal of Geometric Methods in Modern Physics accepted version