Dynamical Dark Energy Emerges from Massive Gravity

Juri Smirnov

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arXiv · 2505.03870

Dynamical Dark Energy Emerges from Massive Gravity

Juri Smirnov

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Abstract

In this work, we demonstrate that a dynamical dark energy component predicted by massive gravity gives rise to a distinctive evolution of the equation of state. This scenario is favoured over the standard $\Lambda$CDM model when confronted with the latest combined datasets from the Dark Energy Spectroscopic Instrument (DESI), the cosmic microwave background (CMB), and supernova observations. The model stands out as a rare example of a healthy, self-consistent theory that accommodates phantom dark energy while maintaining a technically natural, small asymptotic cosmological constant. Our analysis indicates a preferred graviton mass of approximately $4.0 \times 10^{-33} \text{eV}$, suggesting the emergence of a new cosmological length scale. This leads to a maximal deviation of the equation of state around $z \sim 3$, a prediction that will be robustly tested by upcoming, deeper surveys of baryon acoustic oscillations.

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Juri Smirnov. 2025-05-06. Dynamical Dark Energy Emerges from Massive Gravity. https://arxiv.org/abs/2505.03870

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