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Dark energy from coexistence of phases

Ariel Megevand
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Abstract

We suggest that the current acceleration of the universe may be explained by the vacuum energy of a hidden sector which is stuck in a state of equilibrium between phases. The phases are associated to a late-time first-order phase transition, where phase coexistence originates at a temperature $T_c \sim 10^{-3}eV$ and lasts until temperature falls below $T\sim 10^{-4}eV$. During phase coexistence, the energy density has an effective cosmological constant component with the observed magnitude. This scenario does not require supercooling and may arise naturally in realistic models.

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Ariel Megevand. 2006-09-06. Dark energy from coexistence of phases. https://doi.org/10.1016/j.physletb.2006.09.057

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