Logarithmic correction to the Bekenstein-Hawking entropy

The exact formula derived by us earlier for the entropy of a four dimension al nonrotating black hole within the quantum geometry formulation of the ev ent horizon in terms of boundary states of a three dimensional Chern-Simons theory is reexamined for large horizon areas. In addition to the semiclass ical Bekenstein-Hawking contribution proportional to the area obtained earl ier, we find a contribution proportional to the logarithm of the area toget her with subleading corrections that constitute a series in inverse powers of the area.