Glueballs and hybrids are predicted to exist but searches for them have failed to provide conclusive evidence. One–gluon exchange is not an important part of strong interactions in this energy regime. Instead, quarks seem to interact indirectly, via changes of the QCD vacuum. Strong interactions seem to be governed by instanton–induced interactions; the chiral soliton model gives a more suitabl...

We calculate the valence quark distribution functions of π meson using non-relativistic chiral constituent model. The wave function is obtained by solving two-body Schrödinger equation within framework transform from rest frame to light cone or infinite momentum based on Lorentz boost. distributions at initial evolution scale are obtained. QCD given with DGLAP equations parton-parton recombinat...

Since particles such as molecules, atoms and nuclei are composite particles, it is important to recognize that physics must be invariant for the composite particles and their constituent particles, this requirement is called particle invariance in this paper. But difficulties arise immediately because for fermion we use the Dirac equation, for meson we use the Klein-Gordon equation and for clas...