English

$\mathbb{T}^{2}$- inflation: Sourced by energy-momentum squared gravity

General Relativity and Quantum Cosmology 2023-10-20 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

In this paper, we examine chaotic inflation within the context of the energy-momentum squared gravity (EMSG) focusing on the energy-momentum powered gravity (EMPG) that incorporates the functional f(T2)(T2)βf(\mathbb{T}^2)\propto (\mathbb{T}^2)^{\beta} in the Einstein-Hilbert action, in which β\beta is a constant and T2TμνTμν\mathbb{T}^2\equiv T_{\mu \nu}T^{\mu \nu} where TμνT_{\mu \nu} is the energy-momentum tensor, which we consider to represent a single scalar field with a power-law potential. We demonstrate that the presence of EMSG terms allows the single-field monomial chaotic inflationary models to fall within current observational constraints, which are otherwise disfavored by Planck and BICEP/Keck findings. We show that the use of a non-canonical Lagrangian with chaotic potential in EMSG can lead to significantly larger values of the non-Gaussianity parameter, fNlequif_{\rm Nl}^{\rm equi} whereas EMSG framework with canonical Lagrangian gives rise to results similar to those of the standard single-field model.

Keywords

Cite

@article{arxiv.2306.09181,
  title  = {$\mathbb{T}^{2}$- inflation: Sourced by energy-momentum squared gravity},
  author = {Seyed Ali Hosseini Mansoori and Fereshteh Felegary and Mahmood Roshan and Ozgur Akarsu and Mohammad Sami},
  journal= {arXiv preprint arXiv:2306.09181},
  year   = {2023}
}

Comments

25 pages, 4 figures, and 2 tables, added discussion, accepted by Physics of the Dark Universe

R2 v1 2026-06-28T11:06:02.806Z