Physics · Superconductivity & Phase Transitions

In the Landau model of second-order phase transitions, the Helmholtz free energy density expanded near the critical temperature is given by F(m, T) = F0 + αm2 + βm42. Consider the following conditions: 1. The normal state is stable when α > 0, β > 0. 2. The superconducting state occurs when α 0. 3. The minimum free energy in the superconducting state below the critical point is F0 - α22β. Which of these statements are physically correct?