Colour ferromagnetic vacuum state at finite temperature Original Research Article

The spontaneous vacuum magnetization at finite temperature is investigated in SU(2) gluodynamics within a consistent effective potential approach including the one-loop and the correlation correction contributions. To evaluate the latter ones the high temperature limits of the polarization operators of charged and neutral gluon fields in a covariantly constant magnetic field and at high temperature are calculated. The radiation mass squared of charged gluons is found to be positive. It is shown that the ferromagnetic vacuum state having a field strength of order (gH)1/2∼g4/3T is spontaneously generated at high temperature. The correlation corrections increase the field strength as compared to the value (gH)1/2∼g2T determined within the one-loop effective potential. It is also found that the one-loop spectrum of charged gluons calculated for the field derived in one-loop order is stable signalling the vacuum stability in this consistent calculation. The situation with correlation corrections included requires additional investigations. Possible applications of the results obtained are discussed.