Reconstruction and Stability Analysis of Some Cosmological Bouncing Solutions in $F(\mathcal{R},T)$ Theory

TL;DR

This paper explores the reconstruction of $F( ext{R},T)$ gravity models capable of producing various cosmological bouncing solutions, analyzing their stability and energy conditions, and identifying which models yield analytical solutions.

Contribution

It introduces a method to reconstruct $F( ext{R},T)$ functions for bouncing cosmologies and analyzes their stability, providing new insights into viable models in modified gravity.

Findings

Analytical solutions are obtained for exponential, oscillatory, and matter bounce models.

Power law models can be fully reconstructed analytically.

Models are stable only for linear Lagrangian forms, with some power law solutions being unstable.

Abstract

The present article investigates the possibility of reconstruction of the generic function in $F(\mathcal{R},T)$ gravitational theory by considering some well-known cosmological bouncing models namely exponential evaluation, oscillatory, power law and matter bounce model, where $\mathcal{R}$ and $T$ are Ricci scalar and trace of energy-momentum tensor, respectively. Due to the complexity of dynamical field equations, we propose some ansatz forms of function $F(\mathcal{R},T)$ in perspective models and examine that which type of Lagrangian is capable to reproduce bouncing solution via analytical expression. It is seen that for some cases of exponential, oscillatory and matter bounce models, it is possible to get analytical solution while in other cases, it is not possible to achieve exact solutions so only complementary solutions can be discussed. However, for power law model, all forms of generic function can be reconstructed analytically. Further, we analyze the energy conditions and stability of these reconstructed cosmological bouncing models which have analytical forms. It is found that these models are stable for linear forms of Lagrangian only but the reconstructed solutions for power law are unstable for some non-linear forms of Lagrangian.