Doublet-Triplet Splitting and Fat Branes

Abstract

We consider the doublet-triplet splitting problem in supersymmetric SU(5) grand unified theory in five dimensions where the fifth dimension is non-compact. We point out that an unnatural fine-tuning of parameters in order to obtain the light Higgs doublets is not required due to the exponential suppression of the overlap of the wave functions.

Comments: 10 pages, LaTeX, no figures, the version to appear in Phys. Lett. B