Universal Extra Dimensions on Real Projective Plane

We propose a six dimensional Universal Extra Dimensions (UED) model compactified on a real projective plane $R{P}^2$, a two-sphere with its antipodal points being identified. We utilize the Randjbar-Daemi-Salam-Strathdee spontaneous sphere compactification with a monopole configuration of an extra $U(1{)}_X$ gauge field that leads to a spontaneous radius stabilization. Unlike the sphere and the so-called $S^2\mathrm{/}{Z}_2$ compactifications, the massless $U(1{)}_X$ gauge boson is safely projected out. We show how a compactification on a non-orientable manifold results in a chiral four dimensional gauge theory by utilizing 6D chiral gauge and Yukawa interactions. The resultant Kaluza-Klein mass spectra are distinct from the ordinary UED models compactified on torus. We briefly comment on the anomaly cancellation and also on a possible dark matter candidate in our model.