Accelerating universe without event horizon

Pedro F. Gonzalez-Diaz

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Accelerating universe without event horizon

Pedro F. Gonzalez-Diaz

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Abstract

It is shown that if a small negative cosmological constant is added to quintessence models with equation of state $p=ωρ$ on the range $-1 <ω< -1/3$, the resulting scenarios could not contain any future event horizons. Therefore, such cosmological accelerating scenarios could not present the kind of obstacles recently pointed out to define a set of observable quantities analogous to an S-matrix needed by predictive M and string theories in an accelerating universe driven by dark energy. These scenarios become accelerating only at early times after coincidence time, and lead finally to re-collapse.

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Pedro F. Gonzalez-Diaz. 2002-10-08. Accelerating universe without event horizon. https://arxiv.org/abs/astro-ph/0210177

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