  We propose a simple but effective mechanism to realize an inflationary early
universe consistent with the observed WMAP, Planck and/or BICEP2 data, which
would be incorporated in various supersymmetric models of elementary particles
constructed in the (effective) five-dimensional spacetime. In our scenario, the
inflaton field is identified with one of the moduli appearing when the fifth
direction is compactified, and a successful cosmological inflation without the
so-called eta problem can be achieved by a very simple moduli stabilization
potential. We also discuss the related particle cosmology during and (just)
after the inflation, such as the (no) cosmological moduli problem.
