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arXiv · 2306.11101

Metric $f(R)$ gravity with dynamical dark energy as a scenario for the Hubble tension

Giovanni Montani·Mariaveronica De Angelis·Flavio Bombacigno·Nakia Carlevaro
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Abstract

We introduce a theoretical framework to interpret the Hubble tension, based on the combination of a metric $f(R)$ gravity with a dynamical dark energy contribution. The modified gravity provides the non-minimally coupled scalar field responsible for the proper scaling of the Hubble constant, in order to accommodate for the local SNIa pantheon+ data and Planck measurements. The dynamical dark energy source, which exhibits a phantom divide line separating the low red-shift quintessence regime ($-1<w<-1/3$) from the phantom contribution ($w<-1$) in the early Universe, guarantees the absence of tachyonic instabilities at low red-shift. The resulting $H_0(z)$ profile rapidly approaches the Planck value, with a plateau behaviour for $z\gtrsim 5$. In this scenario, the Hubble tension emerges as a low red-shift effect, which can be in principle tested by comparing SNIa predictions with far sources, like QUASARS and Gamma Ray Bursts.

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Giovanni Montani, Mariaveronica De Angelis, Flavio Bombacigno, Nakia Carlevaro. 2023-06-19. Metric $f(R)$ gravity with dynamical dark energy as a scenario for the Hubble tension. https://doi.org/10.1093/mnrasl%2Fslad159

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