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arXiv · 2506.15002

Extended datasamples under the lens of Brane World Theory

Kyra Jacobo·Dorian Araya
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Abstract

This work revises the Brane World Theory known as Randall-Sundrum with the modification of an exponential, redshift-dependent brane tension. This model is studied in a scenario assuming no dark energy, with the aim of determining whether it can reproduce the universe's acceleration on its own, without the addition of a dark energy fluid. Bayesian statistical analysis is performed in order to constrain the free parameters of each scenario using SLS, SNIa, OHD, and BAO data samples, the last two considering newly added data points. Both Planck and Riess priors for h are used and compared. In both cases, we are able to reproduce the late-time accelerated expansion in agreement with observational data. Interesting consistencies at the transition redshift zt with LCDM are found, suggesting that this might be a suitable model for studying the evolution of the universe up to the present date. However, some pathologies are detected in this model, namely a "Big Rip" divergence of H(z) at z = 1, as well as a strong dependence between the functional form of the brane tension and the future evolution of the universe.

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Kyra Jacobo, Dorian Araya. 2025-06-25. Extended datasamples under the lens of Brane World Theory. https://doi.org/10.1088/1361-6382%2Fadda89

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