A Note on Einstein Gravity on AdS${}_3$ and Boundary Conformal Field Theory

We find a simple relation between the first subleading terms in the asymptotic expansion of the metric field in AdS${}_3$, obeying the Brown-Henneaux boundary conditions, and the stress tensor of the underlying Liouville theory on the boundary. We can also provide an more explicit relation between the bulk metric and the boundary conformal field theory when it is described in terms of a free field with a background charge.