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Interest rises to exploit the full shape information of the galaxy powerspectrum, as well as pushing analyses to smaller non-linear scales. Here I usethe halo model to quantify the information content in the tomographic angularpower spectrum of galaxies, for future high resolution surveys : Euclid andSKA2. I study how this information varies as a function of the scale cutapplied, either with angular cut $\ell_{max}$ or physical cut kmax. For this, Iuse analytical covariances with the most complete census of non-Gaussian terms,which proves critical. I find that the Fisher information on most cosmologicaland astrophysical parameters follows a striking behaviour. Beyond theperturbative regime we first get decreasing returns : the information keepsrising but the slope slows down until reaching a saturation. The location ofthis plateau is a bit beyond the reach of current modeling methods : k $\sim$ 2Mpc$^{-1}$ and slightly depends on the parameter and redshift bin considered. Iexplain the origin of this plateau, which is due to non-linear effects both onthe power spectrum, and more importantly on non-Gaussian covariance terms.Then, pushing further we see the information rising again in the highlynon-linear regime, with a steep slope. This is the small scale miracle, forwhich I give interpretation and discuss the properties. Hints are shown thatthis information should be disentanglable from the astrophysical content, andcould improve Dark Energy constraints. Finally, more hints are shown that highorder statistics may yield significant improvements over the power spectrum inthis regime, with the improvements increasing with kmax. Data and notebooksreproducing all plots and results will be made available at\url{https://github.com/fabienlacasa/SmallScaleMiracle}

Cosmology in the non-linear regime : the small scale miracle