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arXiv · 1101.3636

Non-Gaussianity Consistency Relation for Multi-field Inflation

Naonori S. Sugiyama·Eiichiro Komatsu·Toshifumi Futamase
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Abstract

While detection of the "local form" bispectrum of primordial perturbations would rule out all single-field inflation models, multi-field models would still be allowed. We show that multi-field models described by the $δN$ formalism obey an inequality between $f_{\rm NL}$ and one of the local-form {\it trispectrum} amplitudes, $τ_{\rm NL}$, such that $τ_{\rm NL}>\frac12(\frac65f_{\rm NL})^2$ with a possible logarithmic scale dependence, provided that 2-loop terms are small. Detection of a violation of this inequality would rule out most of multi-field models, challenging inflation as a mechanism for generating the primoridal perturbations.

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BibTeXRIS

Naonori S. Sugiyama, Eiichiro Komatsu, Toshifumi Futamase. 2011-05-25. Non-Gaussianity Consistency Relation for Multi-field Inflation. https://doi.org/10.1103/physrevlett.106.251301

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