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arXiv · 2104.06577

A Dark Energy model from Generalized Proca Theory

Chao-Qiang Geng·Yan-Ting Hsu·Jhih-Rong Lu·Lu Yin
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Abstract

We consider a specific dark energy model, which only includes the Lagrangian up to the cubic order in terms of the vector field self-interactions in the generalized Proca theory. We examine the cosmological parameters in the model by using the data sets of CMB and CMB+HST, respectively. In particular, the Hubble constant is found to be $H_0=71.80^{+1.07}_{-0.72}$ ($72.48^{+0.72}_{-0.60}$) $\rm kms^{-1}Mpc^{-1}$ at $68\%$~C.L. with CMB (CMB+HST), which would alleviate the Hubble constant tension. We also obtain that the reduced $\chi^2$ values in our model are close to unity when fitting with CMB and CMB+HST, illustrating that our model is a good candidate to describe the cosmological evolutions of the universe.

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Chao-Qiang Geng, Yan-Ting Hsu, Jhih-Rong Lu, Lu Yin. 2021-04-14. A Dark Energy model from Generalized Proca Theory. https://doi.org/10.1016/j.dark.2021.100819

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