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arXiv · 2103.03949

Role of a periodic varying deceleration parameter in Particle creation with higher dimensional FLRW Universe

Priyanka Garg·Anirudh Pradhan
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Abstract

The present search focus on the mechanism of gravitationally influenced particle creation (PC) in higher dimensional Friedmann-Lemaitre-Robertson-Walker(FLRW) cosmological models with a cosmological constant (CC). The solution of the corresponding field equations is obtained by assuming a periodically varying deceleration parameter (PVDP) i.e. $q= m \cos kt - 1$ [Shen and Zhao, Chin. Phys. Lett., 31 (2014) 010401] which gives a scale factor $a(t) = a_0 \left[\tan \left(\frac{kt}{2}\right)\right]^\frac{1}{m}$, where $a_0$ is the scale factor at the current epoch. Here $k$ displays the PVDP periodicity and can be regarded as a parameter of cosmic frequency, $m$ is an enhancement element that increases the PVDP peak. Here, we investigated the periodic variation behavior of few quantities such as the deceleration parameter $q$, the energy density $\rho$, PC rate $\psi$, the entropy $S$, the CC $\Lambda$, Newton's gravitational constant $G$ and discuss their physical significance. We have also explored the density parameter, proper distance, angular distance, luminosity distance, apparent magnitude, age of the universe, and the look-back time with redshift $z$ and have observed the role of particle formation in-universe evolution in early and late times. The periodic nature of various physical parameters is also discussed which are supporting the recent observations.

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Priyanka Garg, Anirudh Pradhan. 2021-03-04. Role of a periodic varying deceleration parameter in Particle creation with higher dimensional FLRW Universe. https://doi.org/10.1016/j.newast.2022.101821

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