Late-time cosmology of a scalar-tensor theory with a universal multiplicative coupling between the scalar field and the matter Lagrangian
Abstract
We investigate the late-time cosmological behavior of scalar-tensor theories with a universal multiplicative coupling between the scalar field and the matter Lagrangian in the matter era. This class of theory encompasses the case of the massless string dilaton [see Damour and Polyakov, General Relativity and Gravitation 26, 1171 (1994)] as well as a theory with an intrinsic decoupling mechanism in the solar system [see Minazzoli and Hees, Phys. Rev. D 88, 041504 (2013)]. The cosmological evolution is studied in the general relativity limit justified by solar system constraints on the gravitation theory. The behavior of these cosmological evolutions are then compared to two types of observations: the constraints on temporal variations of the constants of nature and the distance-luminosity measurements. In particular, the nonminimal coupling implies that the distance-luminosity relation is modified compared to general relativity. Theories producing a cosmological behavior in agreement with these observations are identified.
- Publication:
-
Physical Review D
- Pub Date:
- July 2014
- DOI:
- 10.1103/PhysRevD.90.023017
- arXiv:
- arXiv:1404.4266
- Bibcode:
- 2014PhRvD..90b3017M
- Keywords:
-
- 95.36.+x;
- 04.50.Kd;
- 04.80.Cc;
- Dark energy;
- Modified theories of gravity;
- Experimental tests of gravitational theories;
- General Relativity and Quantum Cosmology
- E-Print:
- 17 pages - accepted Phys. Rev. D