Perturbation spectrum in inflation with cutoff

As a potentially accessible window to aspects of Planck scale physics it has been pointed out that the perturbation spectrum predicted by inflation may be sensitive to a natural ultraviolet cutoff. A fairly general classification of the possible short-distance cutoffs that one may encounter at the Planck scale has also recently been given. Indeed, various studies of quantum gravity and string theory point towards one of the types of cutoff in this classification. This cutoff has been implemented into the standard inflationary scenario. We here continue this approach by investigating its effects on the predicted perturbation spectrum. We find that the size of the effect depends crucially on the scale separation between cutoff and horizon scales during inflation, becoming negligibly small if the cutoff scale is as small as the Planck length