“…In PT symmetries, the theory may not be invariant under individual transformations of P (which works as x → −x, p → − p ) and T (which works as x → x, p → − p, i → −i), but, under the collective effect of PT , the theory should remain invariant. Apart from the PT operator, Bender et al also pointed out another operator, called the C operator [31], which can be used to remove the ghost states as shown in [32,33]. The existence and completeness of the theory demand that the C-operator should be governed by the three conditions…”