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arXiv · 2107.03271

Phantom braneworld and the Hubble tension

Satadru Bag·Varun Sahni·Arman Shafieloo·Yuri Shtanov
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Abstract

Braneworld models with induced gravity exhibit phantom-like behaviour of the effective equation of state of dark energy. They can, therefore, naturally accommodate higher values of $H_0$, preferred by recent local measurements, while satisfying the CMB constraints. We test the background evolution in such phantom braneworld scenarios with the current observational datasets. We find that the phantom braneworld prefers a higher value of $H_0$ even without the R19 prior, thereby providing a much better fit to the local measurements. Although this braneworld model cannot fully satisfy all combinations of cosmological observables, among existing dark energy candidates the phantom brane provides one of the most compelling explanations of cosmic evolution.

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Satadru Bag, Varun Sahni, Arman Shafieloo, Yuri Shtanov. 2021-07-07. Phantom braneworld and the Hubble tension. https://doi.org/10.3847/1538-4357/ac307e

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