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arXiv · 2010.00513

Proca in the sky

Lavinia Heisenberg·Hector Villarrubia-Rojo
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Abstract

The standard model of cosmology, the $\Lambda$CDM model, describes the evolution of the Universe since the Big Bang with just a few parameters, six in its basic form. Despite being the simplest model, direct late-time measurements of the Hubble constant compared with the early-universe measurements result in the so-called $H_0$ tension. It is claimed that a late time resolution is predestined to fail when different cosmological probes are combined. In this work, we shake the ground of this belief with a very simple model. We show how, in the context of cubic vector Galileon models, the Hubble tension can naturally be relieved using a combination of CMB, BAO and SNe observations without using any prior on $H_0$ . The tension can be reduced even further by including the local measurement of the Hubble constant.

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Lavinia Heisenberg, Hector Villarrubia-Rojo. 2020-10-01. Proca in the sky. https://doi.org/10.1088/1475-7516/2021/03/032

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