The angular ADM reduction of the BTZ spacetime yields a Liouville-type
theory. The analysis of the resulting Liouville theory naturally leads to
identification of the stretched horizon. The dynamics associated with the
stretched horizon has a feature that seems consistent with the unsmooth
horizon; the quantum gravity effects are essential for the unsmoothness. We
show that the "anomaly" term in the stress-energy tensor is responsible for the
Planck scale energy experienced by an infalling observer.Comment: 14 pages, no figure, typos corrected, version to appear in EPJ
