I will describe holographic duals to topologically twisted gauge theories on Riemannian four- and three-manifolds. Imposing boundary conditions for the supergravity fields corresponding to the topological twists, the renormalised supergravity action is independent of the choice of boundary metric. Under additional regularity assumptions, the on-shell action can be evaluated and shown to always vanish, which provides a prediction for the large N limit of topologically twisted theories.

Cambridge University