Finite number of Kaluza-Klein modes, all with zero masses

Abstract

Kaluza-Klein modes of fermions in a 5-dimensional toy model are considered. The number of Kaluza-Klein modes that survive after integration over extra dimensions is finite in this space. Moreover the extra dimensional piece of the kinetic term induces no mass for the higher Kaluza-Klein modes on contrary to the standard lore.Comment: Presentation is improved and typos are corrected, two appendices and some references are added. No change in the essential content of the paper. 11 page