Gauge Couplings Uni cation in Anti-deSitter Space (AdS5) at High Energy Scales

Abstract

In this dissertation, the gauge couplings uni cation in AdS5 was studied. We considered the Standard Model particles to propagate in the bulk of AdS5. The renormalization group equation for the gauge coupling constants at one loop level were derived. We discussed the evolution of inverse ne structure constants 􀀀1 which is related to the gauge coupling constants as well as the evolution of sin2 W; where W is the weak mixing angle in the Weinberg-Salam theory of the electroweak interaction. We found logarithmic running for the gauge coupling constants as in the standard model instead of power law running as in case of at extra dimension models; this result therefore preserving the perturbative uni cation of couplings. We showed that such theory can be compatible with gauge couplings uni cation at high energy scales, these scales at which uni cation occurred were found to be depend strongly on the cuto and on the number of Kaluza-Klein states. Furthermore, we found that sin2 W at this high scales rises up to 0:74 in our model where its value in QFT-subtraction scheme is equals to 0:23; which is a good indicator for the success of our model. These results may be very useful, at least from a model building perspective of gauge couplings uni cation.