It is the equivalent of the phi (strange quark, strange antiquark), psi (charm quark, charm antiquark) and upsilon (bottom quark, bottom antiquark) mesons.
In phi-value analysis, the folding kinetics and conformational folding stability of the wild-type protein are compared with those of one or more point mutants.
A more plausible theory to explain motion perception (at least on a descriptive level) are two distinct perceptual illusions: phi phenomenon and beta movement.
