Talk introducing the topic of gravitational lensing to undergraduate physics students. After a short conceptual and historical introduction we visualize the strong lensing effect of a galaxy cluster. We then move on to introduce the weak lensing effect of cosmic shear and motivate why a large number of sources is neccessary for a detailed reconstruction of the underlying mass field. We close by giving an overview of how this data can be used to get cosmological constraints with stage III surveys and outline the potential of stage IV surveys.
The video used to show the strong lensing effect of a galaxy cluster can be retrieved here.