Comments by "Dr Gamma D" (@DrDeuteron) on "This Particle's Unusual Behavior Is Hinting At Something Big." video.

that's a strange comment.
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@Li.Siyuan particle (P) and antiparticle (A) have the same mass, as made by the strong force, but the weak force acts on the states with small mass splitting: L = xP-yA and a heavy on H = xP+yA, where |x|^2+|y|^2=1, and x or y maybe complex. If |x|=|y|, then L is it's own antiparticle as is H. The best classical analogy is polarized light in a birefringent crystal: H and V pol propagate the same in vacuum, but in the crystal each has a different index of refraction, so the polarization oscillates.
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