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arXiv · 1809.09133

The interacting multiverse and its effect on the cosmic microwave background

Mariam Bouhmadi-López·Manuel Kraemer·João Morais·Salvador Robles-Pérez
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Abstract

We study a toy model of a multiverse consisting of canonically quantized universes that interact with each other on a quantum level based on a field-theoretical formulation of the Wheeler-DeWitt equation. This interaction leads to the appearance of a pre-inflationary phase in the evolution of the individual universes. We analyze scalar perturbations within the model and calculate the influence of the pre-inflationary phase onto the power spectrum of these perturbations. The result is that there is a suppression of power on large scales, which can describe well the Planck 2018 data for the cosmic microwave background anisotropies and could thus indicate a possible solution to the observed quadrupole discrepancy.

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Mariam Bouhmadi-López, Manuel Kraemer, João Morais, Salvador Robles-Pérez. 2018-09-24. The interacting multiverse and its effect on the cosmic microwave background. https://doi.org/10.1088/1475-7516%2F2019%2F02%2F057

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