On exponential modified gravity

Дата и время публикации : 2012-04-27T18:59:13Z

Авторы публикации и институты :
S. I. Kruglov

Ссылка на журнал-издание: Int. J. Mod. Phys.A, Vol.28 (2013), 13501194
Коментарии к cтатье: 20 pages, 9 figures, changed title, extended version, added a section, figures and references, to be published in IJMPA
Первичная категория: gr-qc

Все категории : gr-qc, astro-ph.CO, hep-th

Краткий обзор статьи: A modified theory of gravity with the function $F(R) = Rexp(alpha R)$ instead of Ricci scalar $R$ in the Einstein$-$Hilbert action is considered and analyzed. The action of the model is converted into Einstein$-$Hilbert action at small value of the parameter $alpha$. From local tests we obtain a bound on the parameter $alphaleq 10^{-6}$ cm$^2$. The Jordan and Einstein frames are investigated and the potential of the scalar field in Einstein’s frame is found. The mass of a scalar degree of freedom as a function of curvature is obtained. The static solutions of the model are found corresponding to the Schwarzschild$-$de Sitter space. We show that the de Sitter space is unstable but a solution with zero curvature is stable. The cosmological parameters of the model are calculated. It was demonstrated that the model passes the matter stability test.

Category: Physics