English

The primordial non-Gaussianities for non-singular Horndeski cosmologies

High Energy Physics - Theory 2025-08-26 v4 General Relativity and Quantum Cosmology

Abstract

We consider a novel Bounce Universe model constructed within the framework of Horndeski gravity. We have analyzed the bispectrum of primordial scalar perturbations and evaluated the corresponding non-Gaussianities for this specific model. The non-linear parameter fNLf_{\text{NL}} was computed for various wave vector configurations, including: (i) the local configuration, (ii) the equilateral configuration, and (iii) the enfolded configuration, which is a linear combination of the equilateral and orthogonal shapes. We demonstrate that the observational constraints on the scalar spectrum index tilt and the scalar-to-tensor ratio, together with the unitarity bounds, ensure that the bounds from non-Gaussianities are trivially satisfied. Therefore, this particular Bounce Universe scenario is fully viable in light of modern observational data.

Keywords

Cite

@article{arxiv.2410.10742,
  title  = {The primordial non-Gaussianities for non-singular Horndeski cosmologies},
  author = {Y. Ageeva and M. Kotenko and P. Petrov},
  journal= {arXiv preprint arXiv:2410.10742},
  year   = {2025}
}

Comments

17 pages, 4 figures