The principle of local gauge invariance is applied to fractional wave
equations and the interaction term is determined up to order o(gˉ) in
the coupling constant gˉ. As a first application, based on the
Riemann-Liouville fractional derivative definition, the fractional Zeeman
effect is used to reproduce the baryon spectrum accurately.
The transformation properties of the non relativistic fractional
Schr\"odinger-equation under spatial rotations are investigated and an internal
fractional spin is deduced.Comment: remarks on fractional spin added, references added, in press
Phys.Lett.