Using a recently introduced formalism we discuss slow-roll inflaton from
Kaluza-Klein theory without the cylinder condition. In particular, some
examples corresponding to polynomic and hyperbolic ϕ-potentials are
studied. We find that the evolution of the fifth coordinate should be
determinant for both, the evolution of the early inflationary universe and the
quantum fluctuations.Comment: (final version) to be published in EPJ