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arXiv · 2012.15219

Generalized Holographic Cosmology: low-redshift observational constraint

Sunly Khimphun·Bum-Hoon Lee·Gansukh Tumurtushaa
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Abstract

Four-dimensional cosmological models are studied on a boundary of a five-dimensional Anti-de Sitter (AdS_5) black hole with AdS Reissner-Nordstrom and scalar charged Reissner- Nordstrom black hole solutions, where we call the former a "Hairless" black hole and the latter a "Hairy" black hole. To obtain the Friedmann-Robertson-Walker (FRW) spacetime metric on the boundary of the AdS_5 black hole, we employ Eddington-Finkelstein (EF) coordinates to the bulk geometry. We then derive modified Friedmann equations on a boundary of the AdS_5 black hole via AdS/CFT correspondence and discuss its cosmological implications. The late-time acceleration of the universe is investigated in our models. The contributions coming from the bulk side is treated as a dark energy source, and we perform MCMC analyses using observational data. Compared to the LCDM model, our models contain additional free parameters; therefore, to make a fair comparison, we use the Akaike information criterion (AIC) and the Bayesian information criterion (BIC) to analyze our results. Our numerical analyses show that our models can explain the observational data as reliable as the LCDM model does for the current data.

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Sunly Khimphun, Bum-Hoon Lee, Gansukh Tumurtushaa. 2020-12-30. Generalized Holographic Cosmology: low-redshift observational constraint. https://doi.org/10.1007/jhep10(2021)232

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