Key points are not available for this paper at this time.
It is commonly thought that small couplings in a low-energy theory, such as needed for the fermion mass hierarchy or proton stability, must originate symmetries in a high-energy theory. We show that this expectation is in theories where the Standard Model fields are confined to a thick in extra dimensions, with the fermions "stuck" at different points in the. Couplings between them are then suppressed due to the exponentially small of their wave functions. This provides a framework for understanding the fermion mass hierarchy and proton stability without imposing, but rather in terms of higher dimensional geography. A model prediction of this scenario is non-universal couplings of the Model fermions to the ``Kaluza-Klein'' excitations of the gauge. This allows a measurement of the fermion locations in the extra at the LHC or NLC if the wall thickness is close to the TeV scale.
Arkani–Hamed et al. (Tue,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: