Hadron Spectroscopy (theory): Diquarks, Tetraquarks, Pentaquarks and no   quarks
  States beyond those expected in the simple constituent quark model are now emerging. I focus on the scalar glueball and its mixing with states in the $q\bar{q}$ nonet, and also on correlations in Strong QCD that may form diquarks and seed $qq\bar{q}\bar{q}$ states. Some models of the pentaquark candidate $\Theta(1540)$ are critically discussed. 
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