Enhanced six operations on Artin stacks -- Weizhe Zheng, February 24, 2012

Analogues of Grothendieck's six operations for étale cohomology of Artin stacks have been considered by Behrend, Laszlo, Olsson and others. In recent joint work with Yifeng Liu, we give a general construction of the six operations and prove the base change theorem. After recalling some background, I will explain how higher category theory plays an essential role in our work.