Holographic Description of AdS_2 Black Holes

Understand

We develop the holographic renormalization of AdS_2 gravity systematically.

• We find that a bulk Maxwell term necessitates a boundary mass term for the gauge field and verify that this unusual term is invariant under gauge transformations that preserve the boundary conditions.
• We determine the energy-momentum tensor and the central charge, recovering recent results by Hartman and Strominger.
• We show that our expressions are consistent with dimensional reduction of the AdS_3 energy-momentum tensor and the Brown--Henneaux central charge.