Syed Mudassir Syed Iqbal, G. U. Khapekar, S. R. Bhoyar
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引用次数: 0
Abstract
In this study, we analyze the cosmological evolution of a non-static plane symmetric universe with an exponential scale factor, which drives the phase transition of the universe from deceleration to acceleration, within the framework of f(Q)-gravity, incorporating a perfect fluid. We assume a proportionality condition between the shear scalar \(\sigma \left( t\right) \) and the expansion scalar \(\Theta \left( t\right) \) in order to obtain a determinate cosmological solution of the field equations, leading to a specific relationship between the metric potentials, expressed as \(e^h=s^m\), where m is an arbitrary constant. In the present work, we have studied two \(f\left( Q\right) \)-gravity models: the first \(f\left( Q\right) =\alpha Q+\beta \) is a linear model with free parameters \(\alpha \) and \(\beta \) while the second \(f\left( Q\right) =\left( \alpha Q+\beta \right) e^{-\left( \alpha Q+\beta \right) }\) is a non-linear exponential form with the same free parameters influencing the cosmic behavior. We analyze the physical behavior of both models by examining key cosmological quantities, including the density, pressure, equation of state parameter, deceleration parameter, and jerk parameter. Furthermore, we also analyze the energy conditions to assess the validity of both models, ensuring that they align with the physical requirements of the cosmological framework. We discuss the non-metricity scalar and its physical interpretation. Finally, our models reveal that the universe is in a phase of expansion and acceleration, displaying characteristics similar to a quintessence dark energy model.
期刊介绍:
International Journal of Theoretical Physics publishes original research and reviews in theoretical physics and neighboring fields. Dedicated to the unification of the latest physics research, this journal seeks to map the direction of future research by original work in traditional physics like general relativity, quantum theory with relativistic quantum field theory,as used in particle physics, and by fresh inquiry into quantum measurement theory, and other similarly fundamental areas, e.g. quantum geometry and quantum logic, etc.