Typical domains of propagation (grey areas) given by the Γ(ω) ≥ 0 condition as a function of the gravito-inertial wave frequency ω in a Ω = 0.38Ω_K polytropic model of star. In general, the outer limit of the domain, here loosely represented by the stellar surface, cannot be predicted from ω alone and is obtained by solving the ray dynamics. Panel a) corresponds to a super-inertial frequency (ω>f) and panel b) to a sub-inertial frequency (ω<f). The two bottom figures show domains with an intermediate forbidden zone when frequencies are between the local minimum and maximum of the Brunt-Väisälä frequency. Panel c) corresponds to frequencies in the interval and also exists in non-rotating stars, whereas panel d) corresponds to frequencies in the interval and is due to the centrifugal deformation of rotating stars.