Lensing time delays and cosmological complementarity

Cosmological Constraints from Gravitational Lens Time Delays

Future large ensembles of time delay lenses have the potential to provide interesting cosmological constraints complementary to those of other methods. In a flat universe with constant w including a Planck prior, LSST time delay measurements for ∼ 4, 000 lenses should constrain h to ∼ 0.007 (∼ 1%), Ωde to ∼ 0.005, and w to ∼ 0.026 (all 1-σ precisions). Similar constraints could be obtained by a...

Strong Gravitational Lensing and Dark Energy Complementarity

In the search for the nature of dark energy most cosmological probes measure simple functions of the expansion rate. While powerful, these all involve roughly the same dependence on the dark energy equation of state parameters, with anticorrelation between its present value w0 and time variation wa. Quantities that have instead positive correlation and so a sensitivity direction largely orthogo...

Cosmological Applications of Gravitational Lensing

The last decade has seen an enormous increase of activity in the eld of gravitational lensing, mainly driven by improvements of observational capabilities. I will review the basics of gravitational lens theory, just enough to understand the rest of this contribution, and will then concentrate on several of the main applications in cosmology. Cluster lensing, and weak lensing, will constitute th...

Cosmological Applications of Gravitational Lensing

Distances and lensing in cosmological void models

We study the distances and gravitational lensing in spherically symmetric inhomogeneous cosmological models consisting of inner and outer homogeneous regions which are connected by a single shell or double shells at the redshift z1 ∼ 0.067. The density and Hubble parameters in the inner region are assumed to be smaller and larger, respectively, than those in the outer region. It is found that a...