A geometrical approach to the hadrons and the baryonium

The quark is defined as a flavour vector state in the colour space and the antiquark as a vector in the dual space. The observables appear to be scalar in the colour space built even with a vector and a covector (meson) or with a vector and a pseudovector (baryon). The pseudovector seems to be related to the Pauli-principle existence and allows a comprehension of the distinction between baryons and mesons. The investigation of the strong interaction as exchange of gluons between quarks leads to two fundamental processes: the fusion-fission of mesons and the triple rearrangement of three mesons into a baryon-antibaryon pair. The JOZI rule which forbids the break of a junction is thus recovered. The possible existence of different multiquark states is then considered from the topological point of view. (author)