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arXiv · 2108.00266

MOG cosmology without dark matter and the cosmological constant

Zahra Davari·Sohrab Rahvar
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Abstract

In this work, we investigate the MOdified Gravity (MOG) theory for dynamics of the universe and compare the results with the $Λ$CDM cosmology. We study the background cosmological properties of the MOG model and structure formation at the linear perturbation level. We compare the two models with the currently available cosmological data by using statistical Bayesian analyses. After obtaining updated constraints on the free parameters, we use some methods of model selection to assist in choosing the more consistent model such as the reduced chi-squared ($χ^2_{\rm red}$) and a number of the basic information criteria such as the Akaike Information Criterion (AIC), the Bayes factor or Bayesian Information Criterion (BIC), and Deviance Information Criterion (DIC). MOG model appears to be consistent with the $Λ$CDM model by the results of $χ^2_{\rm red}$ and DIC for an overall statistical analysis using the background data and the linear growth of structure formation.

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Zahra Davari, Sohrab Rahvar. 2021-08-15. MOG cosmology without dark matter and the cosmological constant. https://doi.org/10.1093/mnras%2Fstab2350

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