Large non-Gaussianity from two-component hybrid inflation

By C. Byrnes, Kiwoon Choi, L. M. Hall. 2008

134 citations recorded by the source corpus.

We study the generation of non-Gaussianity in models of hybrid inflation with two inflaton fields, (2-brid inflation). We analyse the region in the parameter and the initial condition space where a large non-Gaussianity may be generated during slow-roll inflation which is generally characterised by a large f_NL, tau_NL and a small g_NL. For certain parameter values we can satisfy tau_NL>>f_NL^2. The bispectrum is of the local type but may have a significant scale dependence. We show that the loop corrections to the power spectrum and bispectrum are suppressed during inflation, if one assume that the fields follow a classical background trajectory. We also include the effect of the waterfall field, which can lead to a significant change in the observables after the waterfall field is destabilised, depending on the couplings between the waterfall and inflaton fields.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/ec2520990bb9cba1f283a2f37b21b403993332d8

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. M. Liguori
2. Kiwoon Choi
3. C. Byrnes
4. J. Fergusson
5. E. Shellard
6. E. Sefusatti
7. D. Seery
8. Xingang Chen

In Nuclear and High Energy Physics

1. Kiwoon Choi
2. C. Byrnes
3. D. Seery
4. J. Fergusson
5. E. Sefusatti
6. E. Shellard
7. M. Liguori
8. Xingang Chen

Citations in the corpus

• Review of local non-Gaussianity from multi-field inflation (2010, methodology): “We have checked in [95] that the correction from the extra expansion which occurs from the surface on which inflation ends up to a surface of uniform energy density is small, and therefore one can still use the δN formalism in this case.”
• Primordial Non-Gaussianity and Bispectrum Measurements in the Cosmic Microwave Background and Large-Scale Structure (2010, background): “More recently, this possibility has been explored as well in models of local non-Gaussianity (Byrnes et al., 2008, 2009a,b; Byrnes & Tasinato, 2009; Kumar et al., 2009).”
• Infrared effects in inflationary correlation functions (2010, background): “Even where a terminal vacuum can be selected in advance, it was shown by Byrnes, Choi and Hall that the final fluctuations may depend sensitively on the path by which the fields arrive at the minimum [134, 135] (reviewed in [136]).”