Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-09-05
Astronomy and Astrophysics
Astrophysics
6 pages, to appear in "Impact of Gravitational Lensing on Cosmology", IAU Symposium 225, Mellier & Meylan eds
Scientific paper
10.1017/S1743921305001894
We present the theory of weak gravitational lensing in cosmologies with generalized gravity, described in the Lagrangian by a generic function depending on the Ricci scalar and a non-minimally coupled scalar field. We work out the generalized Poisson equations relating the dynamics of the fluctuating components to the two gauge invariant scalar gravitational potentials, fixing the new contributions from the modified background expansion and fluctuations. We show how the lensing observables are affected by the cosmic expansion as well as by the presence of the anisotropic stress, which is non-null at the linear level both in scalar-tensor gravity and in theories where the gravitational Lagrangian term features a non-minimal dependence on the Ricci scalar. We derive the generalized expressions for the convergence power spectrum, and illustrate phenomenologically the new effects in Extended Quintessence scenarios, where the scalar field coupled to gravity plays the role of the dark energy.
Acquaviva Viviana
Baccigalupi Carlo
Perrotta Francesca
No associations
LandOfFree
Weak lensing and gravity theories does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Weak lensing and gravity theories, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Weak lensing and gravity theories will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-584419