Chiral Cosmological Model of f(R) Gravity with a Kinetic Curvature Scalar
- 作者: Chervon S.1,2,3, Fomin I.2, Mayorova T.1
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隶属关系:
- Laboratory of Gravitation, Cosmology, Astrophysics
- Department of Physics
- Institute of Physics
- 期: 卷 25, 编号 3 (2019)
- 页面: 205-212
- 栏目: Article
- URL: https://journals.rcsi.science/0202-2893/article/view/176341
- DOI: https://doi.org/10.1134/S0202289319030046
- ID: 176341
如何引用文章
详细
We consider modified f(R) gravity with a kinetic curvature scalar, which can be reduced to a chiral cosmological model of special kind. A detailed derivation is presented for the action of a chiral cosmological model as an equivalent to a gravitational model with higher derivatives with respect to the Ricci scalar using Lagrange multipliers and a transition from the Jordan frame to the Einstein one. The equations of the model are written in the spatially flat Friedmann-Robertson-Walker metric on the basis of the constructed chiral cosmological model. Examples of solutions are found, corresponding to a special choice of the field χ = χ* = const, and its fixed value \(\chi_0=-\sqrt{3/2}\;\text{ln}2\). For this value of χ0, in the case of the canonical inclusion of the kinetic component of the Ricci scalar, we have obtained a nonlinear second-order differential equation with respect to H, which is not amenable to analytic solution. Therefore we implement a transition to a noncanonical form of the kinetic term. Using a fixed value of χ0, an exact solution is obtained for power-law inflation. We have considered a transition from the de Sitter and power-law solutions specified in the Jordan frame to the Einstein frame for comparison with the results obtained in f(R) gravity with higher derivatives. It is proved that there is a Weyl conformal transformation which transforms the de Sitter and power-law solutions in one frame to similar solutions in the other.
作者简介
S. Chervon
Laboratory of Gravitation, Cosmology, Astrophysics; Department of Physics; Institute of Physics
Email: info@pleiadesonline.com
俄罗斯联邦, Ulyanovsk, 432071; Moscow, 105005; Kazan, 420008
I. Fomin
Department of Physics
Email: info@pleiadesonline.com
俄罗斯联邦, Moscow, 105005
T. Mayorova
Laboratory of Gravitation, Cosmology, Astrophysics
Email: info@pleiadesonline.com
俄罗斯联邦, Ulyanovsk, 432071