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arXiv · 0805.3940

Reheating-volume measure for random-walk inflation

Sergei Winitzki
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Abstract

The recently proposed "reheating-volume" (RV) measure promises to solve the long-standing problem of extracting probabilistic predictions from cosmological "multiverse" scenarios involving eternal inflation. I give a detailed description of the new measure and its applications to generic models of eternal inflation of random-walk type. For those models I derive a general formula for RV-regulated probability distributions that is suitable for numerical computations. I show that the results of the RV cutoff in random-walk type models are always gauge-invariant and independent of the initial conditions at the beginning of inflation. In a toy model where equal-time cutoffs lead to the "youngness paradox," the RV cutoff yields unbiased results that are distinct from previously proposed measures.

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Sergei Winitzki. 2008-08-20. Reheating-volume measure for random-walk inflation. https://doi.org/10.1103/physrevd.78.063517

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