Finite temperature behavior of a color ferromagnetic state in QCD

The finite temperature effective potential is computed in the one-loop approximation for a uniform color magnetic classical field configuration (color ferromagnetic vacuum ansatz). Although the real part of the effective potential exhibits a non-trivial minimum, the imaginary part grows indefinitely at high temperature, showing the growing instability of the ansatz. Therefore, the present calculation does not yield a definite conclusion for or against the existence of the phase transition of QCD at finite temperature. (orig.)