Unique contributions to the scalar bispectrum in `just enough inflation’. (arXiv:1906.03942v1 [astro-ph.CO])
<a href="http://arxiv.org/find/astro-ph/1/au:+Ragavendra_H/0/1/0/all/0/1">H.V. Ragavendra</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chowdhury_D/0/1/0/all/0/1">Debika Chowdhury</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sriramkumar_L/0/1/0/all/0/1">L. Sriramkumar</a>
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 $f_{_{rm NL}}$.
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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