Gauge group and phases of superfluid 3He

The p-wave phases of superfluid 3He are classified without the unitary constraint or the constraints on the net nuclear magnetization and the magnetic susceptibility. It is found that two of six p-wave phases are instable against variations of the order parameters when the constraints are relaxed. The order parameters are studied by means of the gauge group and its subgroups. The method used to classify the p-wave phases may be successfully applied to higher pairing states