“…From a phenomenological point of view, the one-dimensional case is the most difficult, since effective diffusion of the neutral mode is weakest in one spatial dimension, such that the effect of inhomogeneity on the far-field is most significant. This phenomenon is well understood in the case of diffusive stability, where decay of localized data is faster in n spatial dimensions (t −n/2 ), or in the case of impurities in oscillatory media, where small impurities can generate wave sources only in dimensions n 2 [9,11,14]. On the other hand, From a technical point of view, the one-dimensional case is easiest since the problem of finding stationary solutions can be cast as an ordinary differential equation (see, for example, [18,24] for this point of view).…”