Dark energy and matter evolution from lensing tomography

Reconstructed from lensing tomography, the evolution of the dark matter density field in the well-understood linear regime can provide model-independent constraints on the growth function of structure and the evolution of the dark energy density. We examine this potential in the context that high-redshift cosmology has in the future been fixed by cosmic microwave background measurements. We construct sharp tests for the existence of multiple dark matter components or a dark energy component that is not a cosmological constant. These functional constraints can be transformed into physically motivated model parameters. From the growth function, the fraction of the dark matter in a smooth component, such as a light neutrino, may be constrained to a statistical precision of sigma(f)approximate to0.0006f(sky)(-1/2) by a survey covering a fraction of sky f(sky) with a redshift resolution Deltaz=0.1. For the dark energy, a parametrization in terms of the present energy density Omega(DE), equation of state w, and its redshift derivative w('), the constraints correspond to sigma(w)=0.009f(sky)(-1/2) and a degenerate combination of the other two parameters. For a fixed Omega(DE), sigma(w('))=0.046f(sky)(-1/2).