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arXiv · 2010.03391

Standard Cosmology on the Anti-de Sitter boundary

Christian Henke
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Abstract

The well-known brane world model of cosmology is an alternative to the standard model of cosmology, called {\Lambda}CDM (Lambda Cold Dark Matter) model. However, the quadratical energy density of the brane universe requires an undesirable fine tuning. The paper develops a new Anti-de Sitter (AdS) brane world model without the quadratical energy density by using a second Einstein equation, which arises canonically during a holographic renormalisation. On the AdS boundary it is demonstrated that this brane model equals an effective de Sitter {\Lambda}CDM model, whereas the brane model near the AdS boundary agrees to the {\Lambda}CDM model except the earliest times. Finally, it is shown that the coincidence problem is avoided and the cosmological constant problem, if not solved, is greatly reduced.

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Christian Henke. 2020-10-06. Standard Cosmology on the Anti-de Sitter boundary. https://doi.org/10.1088/1361-6382%2Fac27ee

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