  Observing the CKM matrix elements written in different parametrization
schemes, one can notice obvious relations among the sine-values of the CP
phases in those schemes. Using the relations, we establish a few
parametrization-independent equations, by which the matrix elements of the CKM
matrix can be completely fixed up to a universal parameter. If it is true, we
expect that there should exist a hidden symmetry in the nature which determines
the relations. Moreover, it requires a universal parameter, naturally it would
be the famous Jarlskog invariant which is also parametrization independent.
Thus the four parameters (three mixing angles and one CP phase) of the CKM
matrix are not free, but determined by the symmetry and the universal
parameter. As we generalize the rules to the PMNS matrix for neutrino mixing,
the CP phase of the lepton sector is predicted to be within a range of $0\sim
59^\circ$ centered at $39^\circ$ (in the P$_a$ parametrization) which will be
tested in the future experiments.

High Energy Physics - Phenomenology;High Energy Physics - Experiment