Prof. Harlow works on black holes and cosmology, viewed through the lens of quantum gravity and quantum field theory.
Recently he has been using methods from quantum information theory to approach these problems, in particular relating the AdS/CFT correspondence, our best theory of quantum gravity so far, to the theory of quantum error correcting codes. He also is working on the symmetry properties of quantum field theory and quantum gravity, in particular the structure of conformal field theories and the phases of gauge theories.