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arXiv · 2006.00244

Hubble Sinks In The Low-Redshift Swampland

Aritra Banerjee·Haiying Cai·Lavinia Heisenberg·Eoin Ó Colgáin·M. M. Sheikh-Jabbari·Tao Yang
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Abstract

Local determinations of the Hubble constant $H_0$ favour a higher value than Planck based on CMB and $\Lambda$CDM. Through a model-independent expansion, we show that low redshift ($z \lesssim 0.7$) data comprising baryon acoustic oscillations (BAO), cosmic chronometers and Type Ia supernovae has a preference for Quintessence models that lower $H_0$ relative to $\Lambda$CDM. In addition, we confirm that an exponential coupling to dark matter cannot alter this conclusion in the same redshift range. Our results leave open the possibility that a coupling in the matter-dominated epoch, potentially even in the dark ages, may yet save $H_0$ from sinking in the string theory Swampland.

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Aritra Banerjee, Haiying Cai, Lavinia Heisenberg, Eoin Ó Colgáin, M. M. Sheikh-Jabbari, Tao Yang. 2020-05-30. Hubble Sinks In The Low-Redshift Swampland. https://doi.org/10.1103/physrevd.103.l081305

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