Testing the Swampland: $H_0$ tension

Eoin Ó Colgáin; Hossein Yavartanoo

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arXiv · 1905.02555

Testing the Swampland: $H_0$ tension

Eoin Ó Colgáin·Hossein Yavartanoo

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Abstract

The de Sitter Swampland conjecture compels us to consider dark energy models where $\lambda(\phi) \equiv |\nabla_{\phi} V|/V$ is bounded below by a positive constant. Moreover, it has been argued for Quintessence models that the constant $\lambda$ scenario is the least constrained. Here we demonstrate that increasing $\lambda$ only exacerbates existing tension in the Hubble constant $H_0$. The identification of dark energy models that both evade observational bounds and alleviate $H_0$ tension constitutes a robust test for the Swampland program.

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Eoin Ó Colgáin, Hossein Yavartanoo. 2019-05-07. Testing the Swampland: $H_0$ tension. https://arxiv.org/abs/1905.02555

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