Scattering amplitudes of the spin-4/3 fractional superstring are shown to satisfy spurious state decoupling and cyclic symmetry (duality) at tree-level in the string perturbation expansion. This fractional superstring is characterized by the spin-4/3 fractional superconformal algebra—a parafermionic algebra studied by Zamolodchikov and Fateev involving chiral spin-4/3 currents on the world-shee...
