Order of Fluctuations of the Free Energy in the SK Model at Critical Temperature

We present an elementary approach to the order of fluctuations for the free energy in the Sherrington-Kirkpatrick mean field spin glass model at and near the critical temperature. It is proved that at the critical temperature the variance of the free energy is of $O((\log N{)}^2)\mathrm{.}$ In addition, we show that if one approaches the critical temperature from the low temperature regime at the rate $O(N^{-\alpha })$ for some $\alpha >0,$ then the variance is of $O((\log N)^2+N^{1-\alpha}).$