  Recent experimental observations are shown to be quantitatively consistent
with an extended concept of space-time having a discrete extra dimension of two
points at the distance of 11.8 fm together with a nontrivial metric structure.
In such a space-time, fermions appear in pair with their Kaluza-Klein siblings.
The usual electromagnetic field is accompanied with a new vector boson $X17$,
which receives a mass of $17~MeV$ from another Kaluza-Klein partner, a scalar
boson $H$ of a mass in the range of $0.5-793~keV$ via an abelian Higgs
mechanism. At a low energy scale, where nucleons can be treated as
structureless in a good approximation, the natural particle model involving
nucleons, electron, neutrino and their Kaluza-Klein partners coupled to the
electromagnetic field and the massive vector boson $X7$ can lead to new
phenomenological consequences, which are verifiable at the currently accessible
energy.
