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arXiv · 2310.11413

Exploring Late-Time Cosmic Acceleration with EoS Parameterizations in Horava-Lifshitz Gravity via Baryon Acoustic Oscillations

Abstract

In our study, we have adopted the framework of Horava-Lifshitz gravity to model the Universe's dark matter and dark energy components. Specifically, we have considered two recent parametrizations for dark energy models: the CBDRM-type and CADMM-type parameterizations. In our analysis, we have explicitly expressed the Hubble parameter, denoted as $H(z)$, for these two distinct dark energy models. By doing so, we have aimed to investigate and quantify the accelerated cosmic expansion rate characterizing the late-time Universe. Our study uses a wide range of datasets. This dataset consists of recent measurements of baryon acoustic oscillations (BAO) collected over a period of twenty years with the Cosmic Chronometers (CC) dataset, Type Ia supernovae (SNIa) dataset, the Hubble diagram of gamma-ray bursts (GRBs), quasars (Q), and the latest measurement of the Hubble constant (R22). Consequently, we present a crucial aspect of our study by plotting the $r_{d}$ vs. $H_{0}$ plane. In the context of the $Λ$CDM model, after incorporating all the datasets, including the R22 prior, we obtain the following results: $H_{0}$ = $71.674089 \pm 0.734089$ $km s^{-1} Mpc^{-1}$ and $r_d = 143.050380 Mpc \pm 3.702038$. For the CBDRM model, we find $H_{0}$ = $72.355058 \pm 1.004604$ $km s^{-1} Mpc^{-1}$ and $r_d = 144.835069 Mpc \pm 2.378848$. In the case of the CADMM model, our analysis yields $H_{0}$ = $72.347804 \pm 0.923328$ $km s^{-1} Mpc^{-1}$ and $r_d = 144.466836 Mpc \pm 4.288758$. We have conducted cosmographic analyses for both of the proposed parameterizations in comparison to the $Λ$CDM paradigm. Additionally, we have applied Diagnostic tests to investigate the evolution of both models. Finally, the Information Criteria test demonstrates that the $Λ$CDM model emerges as the preferred choice among the models we have considered.

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Madhur Khurana, Himanshu Chaudhary, Ujjal Debnath, Alok Sardar, G. Mustafa. 2023-10-17. Exploring Late-Time Cosmic Acceleration with EoS Parameterizations in Horava-Lifshitz Gravity via Baryon Acoustic Oscillations. https://arxiv.org/abs/2310.11413

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