The pomeron conjecture and two gluon glueballs
  In this talk the pomeron conjecture is reviewed and constituent gluon models are derived. In a simple two-gluon glueball spectrum the pomeron trajectory and the daughter trajectories are computed. The open problems of two-gluon glueballs are discussed, including transversality and Yang's theorem, the spin tensor interactions, the structure of the string and decays. The related systems of charmed hybrids and of the gluelump are also addressed. To conclude, different aspects of glueballs that could be measured at PANDA are highlighted. 
P. Bicudo