Modelling the outskirts of galaxies in a cosmological context

Current data broadly support trends of galaxy surface brightness profile amplitude and shape with total stellar mass predicted by state-of-the-art Lambda-CDM cosmological simulations, although recent results show signs of interesting discrepancies, particularly for galaxies less massive than the Milky Way. Here I discuss how perhaps the largest contribution to such discrepancies can be inferred almost directly from how well a given model agrees with the observed present-day galaxy stellar mass function.