 CP-symmetry states that the laws of physics should be the same if a particle were interchanged with its antiparticle (C symmetry, as charges of antiparticles are the negative of the corresponding particle), and then left and right were swapped (P symmetry).Experiments do not indicate any CP violation in the QCD sector.For example, a generic CP violation in the strongly interacting sector would create an electric dipole moment of the neutron which would be comparable to 10−18 e·m while the current experimental upper bound is roughly one billionth that size.