I will present measurements of gravitational lensing from the Sloan Digital Sky Survey and the Dark Energy Survey. We use new methods to measure the mass distribution and clustering of cosmic voids and the shapes of galaxy halos.
With the Dark Energy Survey and CMB data, we have made wide field mass maps and related the galaxy distribution to the dark matter. Ideas that provide alternatives to the standard cosmological model include the possibility that gravity on large scales deviates from general relativity or that dark matter has new interactions. I will describe how a variety of measurements are used to pursue such new physics.