We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational constant and the cosmological constant etc. are generated by a solution of the classical equations of motion which breaks scale invariance. In this paper we demonstrate the stability of such a solution against small perturbations in a flat FRW background by making a perturbative expansion around this solution and solving the resulting equations linear in the perturbations.
Cosmological perturbation analysis in a scale invariant model of gravity / Jain, Pankaj; Karmakar, Purnendu; Mitra, Subhadip; Panda, Sukanta; Singh, Naveen K. - In: CLASSICAL AND QUANTUM GRAVITY. - ISSN 0264-9381. - 28:21(2011), p. 215010. [10.1088/0264-9381/28/21/215010]
Cosmological perturbation analysis in a scale invariant model of gravity
Karmakar, Purnendu
;
2011
Abstract
We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational constant and the cosmological constant etc. are generated by a solution of the classical equations of motion which breaks scale invariance. In this paper we demonstrate the stability of such a solution against small perturbations in a flat FRW background by making a perturbative expansion around this solution and solving the resulting equations linear in the perturbations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.