Area law for black hole entropy in the SU(2) quantum geometry approach
  Black hole thermodynamics suggests that a black hole should have an entropy given by a quarter of the area of its horizon. Earlier calculations in U(1) loop quantum gravity have led to a dominant term proportional to the area, but there was a correction involving the logarithm of the area. We find however that SU(2) loop quantum gravity can provide an entropy that is strictly proportional to the area as expected from black hole thermodynamics. 
P. Mitra
gr-qc hep-th