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arXiv · hep-th/9705035

Pre-Big-Bang Inflation Requires Fine Tuning

Michael S. Turner·Erick J. Weinberg
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Abstract

The pre-big-bang cosmology inspired by superstring theories has been suggested as an alternative to slow-roll inflation. We analyze, in both the Jordan and Einstein frames, the effect of spatial curvature on this scenario and show that too much curvature --- of either sign --- reduces the duration of the inflationary era to such an extent that the flatness and horizon problems are not solved. Hence, a fine-tuning of initial conditions is required to obtain enough inflation to solve the cosmological problems.

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Michael S. Turner, Erick J. Weinberg. 1997-05-06. Pre-Big-Bang Inflation Requires Fine Tuning. https://doi.org/10.1103/physrevd.56.4604

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