English

Anisotropic solutions for $R^2$ gravity model with a scalar field

General Relativity and Quantum Cosmology 2024-03-01 v2 Cosmology and Nongalactic Astrophysics Mathematical Physics math.MP

Abstract

We study anisotropic solutions for the pure R2R^2 gravity model with a scalar field in the Bianchi I metric. The evolution equations have a singularity at zero value of the Ricci scalar RR for anisotropic solutions, whereas these equations are smooth for isotropic solutions. So, there is no anisotropic solution with the Ricci scalar smoothly changing its sign during evolution. We have found anisotropic solutions using the conformal transformation of the metric and the Einstein frame. The general solution in the Einstein frame has been found explicitly. The corresponding solution in the Jordan frame has been constructed in quadratures.

Keywords

Cite

@article{arxiv.2301.06836,
  title  = {Anisotropic solutions for $R^2$ gravity model with a scalar field},
  author = {Vsevolod R. Ivanov and Sergey Yu. Vernov},
  journal= {arXiv preprint arXiv:2301.06836},
  year   = {2024}
}

Comments

13 pages, accepted for publication in Phys. Atom. Nuclei

R2 v1 2026-06-28T08:13:21.987Z