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Quantum creation and inflationary universes: a critical appraisal

D. H. Coule
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Abstract

We contrast the possibility of inflation starting a) from the universe's inception or b) from an earlier non-inflationary state. Neither case is ideal since a) assumes quantum mechanical reasoning is straightforwardly applicable to the early universe; while case b) requires that a singularity still be present. Further, in agreement with Vachaspati and Trodden [1] case b) can only solve the horizon problem if the non-inflationary phase has equation of state $γ<4/3$.

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D. H. Coule. 2000-07-17. Quantum creation and inflationary universes: a critical appraisal. https://doi.org/10.1103/physrevd.62.124010

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