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arXiv · 1906.03942

Unique contributions to the scalar bispectrum in `just enough inflation'

H. V. Ragavendra·Debika Chowdhury·L. Sriramkumar
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Abstract

A scalar field rolling down a potential with a large initial velocity results in inflation of a finite duration. Such a scenario suppresses the scalar power on large scales improving the fit to the cosmological data. We find that the scenario leads to a hitherto unexplored situation wherein the boundary terms dominate the contributions to the scalar bispectrum over the bulk terms. We show that the consistency relation governing the non-Gaussianity parameter $f_{_{\rm NL}}$ is violated on large scales and that the contributions at the initial time can substantially enhance the value of $f_{_{\rm NL}}$.

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H. V. Ragavendra, Debika Chowdhury, L. Sriramkumar. 2019-06-10. Unique contributions to the scalar bispectrum in `just enough inflation'. https://doi.org/10.1007/978-981-15-6292-1_5

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