Anticipating the higher generations of quarks from rephasing invariance of the mixing matrix

Abstract We show that the number of invariant CP violating parameters X CP jumps from the unique universal one in three generations to nine in the four-generation case, saturating the parameter space for generation numbers higher than three. This can lead to drastically different consequences in CP -violating phenomena. We give the quark mass matrices in the three-generation case and speculate for higher generations. We also give some invariant definitions of “maximal” CP violation.