  We have calculated the free energy up to two loop to compare T^2 with T^4 in
IIB matrix model. It turns out that T^2 has smaller free energy than T^4. We
have also discussed the generation of the gauge group by considering
k-coincident fuzzy tori and found that in this case U(1) gauge group is
favored. This means that if the true vacuum is four-dimensional, it is not a
simple fuzzy space considered here.
