The "What is it?" obsession.


Quark-antiquark?
Two-meson molecule?
Glueball?
Tetraquark?
Hexaquark?
etc.
Hadronic states are just mixtures of all that!
We show that the first two components are the most relevant.
Moreover, a resonance is a collection of states,
all with different masses.
Each of those states will have a different composition.