Unbiasing cosmology for future LSS surveys by understanding baryonic effects at high wavenumber

Accurate theoretical prediction of galaxy clustering on small scales is challenging due to the effects on baryons. These effects dramatically vary as a function of scale, increasing sharply with wavenumber $k$ as previously shown with simulations and, to some extent, measurements of galaxy clustering and weak-lensing shear. We investigate, using a combination of analytical and numerical tools, the accuracy with which baryonic effects will need to be understood in order not to bias the cosmological constraints from forthcoming surveys of large-scale structure.