English

Non-Gaussianity from Symmetry

Astrophysics 2009-06-23 v2 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

Abstract

We point out that a light scalar field fluctuating around a symmetry-enhaced point can generate large non-Gaussianity in density fluctuations. We name such a particle as an "ungaussiton", a scalar field dominantly produced by the quantum fluctuations,generating sizable non-Gaussianity in the density fluctuations. We derive a consistency relation between the bispectrum and the trispectrum, tau_NL = 10^3 f_NL^(4/3), which can be extended to arbitrary high order correlation functions. If such a relation is confirmed by future observations, it will strongly support this mechanism.

Keywords

Cite

@article{arxiv.0804.0425,
  title  = {Non-Gaussianity from Symmetry},
  author = {Teruaki Suyama and Fuminobu Takahashi},
  journal= {arXiv preprint arXiv:0804.0425},
  year   = {2009}
}

Comments

26 pages, 1 figure;v2 discussion and references added. To appear in JCAP

R2 v1 2026-06-21T10:27:07.641Z