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arXiv · hep-th/0404109

Accelerated expansion and the Goldstone ghost

B. Holdom
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Abstract

A vacuum instability due to a massless ghost in a hidden sector can lead to an effective equation of state for dark energy that changes smoothly from $w=-3/2$ at large redshifts, to $w\approx-1.2$ today, to $w=-1$ in the future. We discuss how this ghost can be the Goldstone boson of Lorentz symmetry breaking, and we find that this breaking in the hidden sector should occur at a scale below $\sim$10 KeV. The normal particles that are produced along with the ghosts are then predominantly neutrinos.

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B. Holdom. 2004-09-02. Accelerated expansion and the Goldstone ghost. https://doi.org/10.1088/1126-6708%2F2004%2F07%2F063

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