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arXiv · hep-th/0601162

Probabilities in the Bousso-Polchinski multiverse

Delia Schwartz-Perlov·Alexander Vilenkin
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Abstract

Using the recently introduced method to calculate bubble abundances in an eternally inflating spacetime, we investigate the volume distribution for the cosmological constant $Λ$ in the context of the Bousso-Polchinski landscape model. We find that the resulting distribution has a staggered appearance which is in sharp contrast to the heuristically expected flat distribution. Previous successful predictions for the observed value of $Λ$ have hinged on the assumption of a flat volume distribution. To reconcile our staggered distribution with observations for $Λ$, the BP model would have to produce a huge number of vacua in the anthropic range $ΔΛ_A$ of $Λ$, so that the distribution could conceivably become smooth after averaging over some suitable scale $δΛ\llΔΛ_A$.

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Delia Schwartz-Perlov, Alexander Vilenkin. 2006-05-04. Probabilities in the Bousso-Polchinski multiverse. https://doi.org/10.1088/1475-7516%2F2006%2F06%2F010

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