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arXiv · 2201.06866

Cosmological constrains on new generalized Chaplygin gas model

Fataneh Salahedin·Reza Pazhouhesh·Mohammad Malekjani
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Abstract

We use different combinations of data samples to investigate the new generalized Chaplygin gas (NGCG) model in the context of dark energy (DE) cosmology. Using the available cosmological data, we put constraints on the the free parameters of NGCG model based on the statistical Markov chain Monte Carlo method. We then find the best fit values of cosmological parameters and those confidence regions in NGCG cosmology. Our result for the matter density parameter calculated in NGCG model is in excellent agreement with that of the standard CDM cosmology. We also find that the equation of state of DE of the model slightly favors the phantom regime. We show that the big tension between the low- and high-redshift observations appearing in CDM universe to predict the Hubble constant H 0 can be alleviated in NGCG model. However, from the statistical point of view, our results show that the standard CDM model fits the observations better than the NGCG cosmology.

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Fataneh Salahedin, Reza Pazhouhesh, Mohammad Malekjani. 2022-01-18. Cosmological constrains on new generalized Chaplygin gas model. https://arxiv.org/abs/2201.06866

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