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arXiv · 1311.1575

Non-Gaussianity Consistency Relations, Initial States and Back-reaction

Sandipan Kundu
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Abstract

We explore the consistency relations for the three-point functions, in the squeezed limit, of scalar and tensor perturbations in single-field inflation with general initial conditions for the perturbations. For slow-roll inflation, we find that all the three-point functions of scalar and tensor perturbations with a coherent state as the initial state are identical to the three-point functions with the Bunch-Davies initial state. On the other hand, there is an apparent violation of some of the consistency relations for initial states that are related to the Bunch-Davies state by Bogoliubov transformations and we identify the reason for this violation. The back-reaction calculations indicate that the three-point functions for these states can be large enough to violate the consistency relations, however, they are too small to be observed in the near future.

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Sandipan Kundu. 2013-11-07. Non-Gaussianity Consistency Relations, Initial States and Back-reaction. https://doi.org/10.1088/1475-7516%2F2014%2F04%2F016

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