Testing the DGP model with gravitational lensing statistics
Abstract
Aims: The self-accelerating braneworld model (DGP) appears to provide a simple alternative to the standard ΛCDM cosmology to explain the current cosmic acceleration, which is strongly indicated by measurements of type Ia supernovae, as well as other concordant observations.
Methods: We investigate observational constraints on this scenario provided by gravitational-lensing statistics using the Cosmic Lens All-Sky Survey (CLASS) lensing sample.
Results: We show that a substantial part of the parameter space of the DGP model agrees well with that of radio source gravitational lensing sample.
Conclusions: In the flat case, Ω_K=0, the likelihood is maximized, L=L_max, for ΩM = 0.30-0.11+0.19. If we relax the prior on Ω_K, the likelihood peaks at Ω_M,Ωr_c ≃ 0.29, 0.12, slightly in the region of open models. The confidence contours are, however, elongated such that we are unable to discard any of the close, flat or open models.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- September 2008
- DOI:
- 10.1051/0004-6361:200809386
- arXiv:
- arXiv:0804.2917
- Bibcode:
- 2008A&A...487..831Z
- Keywords:
-
- cosmological parameters;
- cosmology: theory;
- gravitational lensing;
- quasars: general;
- Astrophysics
- E-Print:
- 5 pages, 2 figures, accepted for publication in A&