I will summarise the evidence for dark energy and the basics of cosmic shear. My talk will then focus on how to obtain the maximum constraining power from the upcoming experiments to measure dark energy using cosmic shear. I will introduce the GRavitational lEnsing Accuracy Testing 2008 (GREAT08) Challenge, which is an image analysis competition to improve shear measurements. I will also describe the potentially confusing signal from intrinsic galaxy alignments and how it can be addressed.
UCL