Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields

Details Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields

2009-06-26

arxiv.org/abs/0906.4944v2

JCAP 0910:015,2009

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

31 pages, 2 figures. This version matches the one in press by JCAP

Scientific paper

10.1088/1475-7516/2009/10/015

We consider a primordial SU(2) vector multiplet during inflation in models where quantum fluctuations of vector fields are involved in producing the curvature perturbation. Recently, a lot of attention has been paid to models populated by vector fields, given the interesting possibility of generating some level of statistical anisotropy in the cosmological perturbations. The scenario we propose is strongly motivated by the fact that, for non-Abelian gauge fields, self-interactions are responsible for generating extra terms in the cosmological correlation functions, which are naturally absent in the Abelian case. We compute these extra contributions to the bispectrum of the curvature perturbation, using the delta N formula and the Schwinger-Keldysh formalism. The primordial violation of rotational invariance (due to the introduction of the SU(2) gauge multiplet) leaves its imprint on the correlation functions introducing, as expected, some degree of statistical anisotropy in our results. We calculate the non-Gaussianity parameter f_{NL}, proving that the new contributions derived from gauge bosons self-interactions can be important, and in some cases the dominat ones. We study the shape of the bispectrum and we find that it turns out to peak in the local configuration, with an amplitude that is modulated by the preferred directions that break statistical isotropy.

Affiliated with

Also associated with

No associations

Rating

Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-671028