Bounded dark energy
Phys. Rev. D 112, 023521 – Published 15 July, 2025
DOI: https://doi.org/10.1103/tscs-h4xv
Abstract
Recent cosmological observations suggest that the dark energy equation of state may have changed in the latter stages of cosmic history. We introduce a quintessence scenario, termed bounded dark energy, capable of explaining this feature in a technically natural way. Our approach is motivated from a bottom-up perspective, based on the concept of mirage cutoff, where we demonstrate the stability of the quintessence potential against large quantum corrections. At the same time, the bounded dark energy framework aligns well with top-down considerations motivated from quantum gravity arguments. We employ both human-driven insights and machine learning techniques to identify explicit realizations of bounded dark energy models. We then perform an analysis based on Markov Chain Monte Carlo method to assess their predictions against cosmic microwave background, galaxy surveys, and supernova data, showing that bounded dark energy provides a good fit to current observations. We also discuss how upcoming measurements can further test and refine our proposal.