AdS3/CFT2: Weyl anomaly, central charge c, and bulk conformal factor
In AdS3/CFT2, the Brown-Henneaux formula c=3l/(2G_N) relates the CFT central charge to the AdS radius. The Weyl anomaly T^mu_mu = -c/(12pi)*R generates a conformal factor phi that backreacts on the bulk metric. The stress tensor two-point function G(x)~c/x^4 is computed holographically from the bulk-to-boundary propagator.