Testing orbifold models of Supersymmetric Grand Unification

In a model of supersymmetric SU(5) Grand Unification with a spatial dimension described by the orbifold $S^1\mathrm{/}(Z_2\times Z_2^{\mathrm{\prime }})$, proton decay is naturally suppressed at all orders. This is achieved by a suitable implementation of the discrete symmetries on the brane. But baryon number violating interactions are present in this model. We propose a few possible experimental tests of this model which exploit the effect of the baryon number violating couplings on low-energy observables like neutron-antineutron oscillations, double nucleon decay into two kaons, hadronic decay widths of the $Z$ boson, and $t\bar{t}$ production cross-section in Run II of the Tevatron.