We develop a stochastic approach to study scalar field fluctuations of the
inflaton field in an early inflationary universe with a black-hole (BH), which
is described by an effective 4D SdS metric. Considering a 5D Ricci-flat SdS
static metric, we implement a planar coordinate transformation, in order to
obtain a 5D cosmological metric, from which the effective 4D SdS metric can be
induced on a 4D hypersurface. We found that at the end of inflation, the
squared fluctuations of the inflaton field are not exactly scale independent
and becomes sensitive with the mass of the BH.Comment: version accepted in European Physical Journal Plu